diff --git a/examples/webhooks/src/services/conversation.service.ts b/examples/webhooks/src/services/conversation.service.ts
index 6d2d1244..fc74e664 100644
--- a/examples/webhooks/src/services/conversation.service.ts
+++ b/examples/webhooks/src/services/conversation.service.ts
@@ -24,35 +24,39 @@ export class ConversationService {
   };
 
   private buildTextMessage(contactMessage: ContactMessage) {
-    if ('text_message' in contactMessage) {
+    if ('text_message' in contactMessage && contactMessage.text_message) {
       return messageBuilder.text({
         text: `Parrot mode 🦜: ${contactMessage.text_message.text}`,
       });
     }
-    if ('media_message' in contactMessage) {
+    if ('media_message' in contactMessage && contactMessage.media_message) {
       return messageBuilder.media({
         url: contactMessage.media_message.url,
       });
     }
-    if ('fallback_message' in contactMessage) {
+    if ('fallback_message' in contactMessage && contactMessage.fallback_message && contactMessage.fallback_message.reason) {
       return messageBuilder.text({
         text: `Error: ${contactMessage.fallback_message.reason.code} (${contactMessage.fallback_message.reason.sub_code})\n${contactMessage.fallback_message.reason.description}`
       });
     }
+    return messageBuilder.text({
+      text: `Impossible to handle the incoming message`,
+    });
   }
 
   handleEvent(event: ConversationWebhookEventParsed): void {
     switch (event.trigger) {
       case 'MESSAGE_INBOUND':
         console.log('\n## MESSAGE_INBOUND');
-        const contactMessage = event.message.contact_message;
-        const channelIdentityTo = event.message.channel_identity;
-        console.log(`A new message has been received on the channel '${channelIdentityTo.channel}' (identity: ${channelIdentityTo.identity}) from the contact ID '${event.message.contact_id}':\n${JSON.stringify(contactMessage, null, 2)}`);
+        const message = event.message!;
+        const contactMessage = message.contact_message!;
+        const channelIdentityTo = message.channel_identity!;
+        console.log(`A new message has been received on the channel '${channelIdentityTo.channel}' (identity: ${channelIdentityTo.identity}) from the contact ID '${message.contact_id}':\n${JSON.stringify(contactMessage, null, 2)}`);
         const requestData: SendMessageRequestData = {
           sendMessageRequestBody: {
-            app_id: event.app_id,
+            app_id: event.app_id!,
             recipient: {
-              contact_id: event.message.contact_id,
+              contact_id: message.contact_id,
             },
             message: this.buildTextMessage(contactMessage),
             ttl: '5s',
@@ -67,24 +71,26 @@ export class ConversationService {
         break;
       case 'MESSAGE_INBOUND_SMART_CONVERSATION_REDACTION':
         console.log('\n## MESSAGE_INBOUND_SMART_CONVERSATION_REDACTION');
-        if ('text_message' in event.message_redaction.contact_message) {
-          console.log(`A.I. analyzed and redacted message:\n${event.message_redaction.contact_message.text_message.text}`);
+        const messageRedaction = event.message_redaction!;
+        if ('text_message' in messageRedaction.contact_message!) {
+          console.log(`A.I. analyzed and redacted message:\n${messageRedaction.contact_message.text_message!.text}`);
         }
         break;
       case 'MESSAGE_SUBMIT':
         console.log('\n## MESSAGE_SUBMIT');
-        const submittedMessage = event.message_submit_notification.submitted_message;
-        const channelIdentityFrom = event.message_submit_notification.channel_identity;
-        console.log(`The following message has been submitted on the channel '${channelIdentityFrom.channel}' (identity: ${channelIdentityFrom.identity}) to the contact ID '${event.message_submit_notification.contact_id}':\n${JSON.stringify(submittedMessage, null, 2)}`);
+        const messageSubmitNotification = event.message_submit_notification!;
+        const submittedMessage = messageSubmitNotification.submitted_message!;
+        const channelIdentityFrom = messageSubmitNotification.channel_identity!;
+        console.log(`The following message has been submitted on the channel '${channelIdentityFrom.channel}' (identity: ${channelIdentityFrom.identity}) to the contact ID '${messageSubmitNotification.contact_id}':\n${JSON.stringify(submittedMessage, null, 2)}`);
         break;
       case 'SMART_CONVERSATIONS':
         console.log('\n## SMART_CONVERSATIONS');
-        const analysisResult = event.smart_conversation_notification.analysis_results;
+        const analysisResult = event.smart_conversation_notification!.analysis_results!;
         if (analysisResult.ml_sentiment_result) {
           console.log(`The sentiment of the message is '${analysisResult.ml_sentiment_result[0].sentiment}' with a score of ${analysisResult.ml_sentiment_result[0].score}`);
         }
         if (analysisResult.ml_nlu_result) {
-          console.log(`The intent of the message is '${analysisResult.ml_nlu_result[0].intent}' with a score of ${analysisResult.ml_nlu_result[0].score}. Other intents are:\n${analysisResult.ml_nlu_result[0].results.map((result) => '- ' + result.intent + ': ' + result.score).join('\n')}`);
+          console.log(`The intent of the message is '${analysisResult.ml_nlu_result[0].intent}' with a score of ${analysisResult.ml_nlu_result[0].score}. Other intents are:\n${analysisResult.ml_nlu_result[0].results?.map((result) => '- ' + result.intent + ': ' + result.score).join('\n')}`);
         }
         if (analysisResult.ml_pii_result) {
           console.log(`Message with masked PII:\n${analysisResult.ml_pii_result[0].masked}`);
@@ -98,100 +104,105 @@ export class ConversationService {
         break;
       case 'MESSAGE_DELIVERY':
         console.log('\n## MESSAGE_DELIVERY');
-        const messageDeliveryStatus = event.message_delivery_report.status;
+        const messageDelivery = event.message_delivery_report!;
+        const messageDeliveryStatus = messageDelivery.status;
         console.log(`Message delivery status: '${messageDeliveryStatus}'`);
         if ('FAILED' === messageDeliveryStatus) {
-          const failedDeliveryReason = event.message_delivery_report.reason;
+          const failedDeliveryReason = messageDelivery.reason!;
           console.log(`Reason: ${failedDeliveryReason.code} (${failedDeliveryReason.sub_code})`);
           console.log(`Description: ${failedDeliveryReason.description}`);
         }
         break;
       case 'EVENT_INBOUND':
         console.log('\n## EVENT_INBOUND');
-        if ('contact_event' in event.event) {
-          console.log(`A new contact event has been received on the channel '${event.event.channel_identity.channel}' (${event.event.channel_identity.identity}) from the contact ID '${event.event.contact_id}'`);
+        const inboundEvent = event.event!;
+        if ('contact_event' in inboundEvent) {
+          console.log(`A new contact event has been received on the channel '${inboundEvent.channel_identity?.channel}' (${inboundEvent.channel_identity?.identity}) from the contact ID '${inboundEvent.contact_id}'`);
         }
-        if ('contact_message_event' in event.event) {
-          const contactMessageEvent = event.event.contact_message_event;
-          console.log(`A new contact message event has been received on the channel '${event.event.channel_identity.channel}' (${event.event.channel_identity.identity}) from the contact ID '${event.event.contact_id}'`);
-          console.log(`Payment status: ${contactMessageEvent.payment_status_update_event.payment_status}`);
+        if ('contact_message_event' in inboundEvent) {
+          const contactMessageEvent = inboundEvent.contact_message_event!;
+          console.log(`A new contact message event has been received on the channel '${inboundEvent.channel_identity?.channel}' (${inboundEvent.channel_identity?.identity}) from the contact ID '${inboundEvent.contact_id}'`);
+          console.log(`Payment status: ${contactMessageEvent.payment_status_update_event?.payment_status}`);
         }
         break;
       case 'EVENT_DELIVERY':
         console.log('\n## EVENT_DELIVERY');
-        const eventDeliveryStatus = event.event_delivery_report.status;
+        const eventDeliveryReport = event.event_delivery_report!;
+        const eventDeliveryStatus = eventDeliveryReport.status;
         console.log(`Event delivery status: '${eventDeliveryStatus}'`);
         if ('FAILED' === eventDeliveryStatus) {
-          const failedDeliveryReason = event.event_delivery_report.reason;
+          const failedDeliveryReason = eventDeliveryReport.reason!;
           console.log(`Reason: ${failedDeliveryReason.code} (${failedDeliveryReason.sub_code})`);
           console.log(`Description: ${failedDeliveryReason.description}`);
         }
         break;
       case 'CONVERSATION_START':
         console.log('\n## CONVERSATION_START');
-        const conversationStart  = event.conversation_start_notification.conversation;
+        const conversationStart  = event.conversation_start_notification!.conversation!;
         console.log(`The conversation '${conversationStart.id}' has started on the channel ${conversationStart.active_channel}`);
         break;
       case 'CONVERSATION_STOP':
         console.log('\n## CONVERSATION_STOP');
-        const conversationStop = event.conversation_stop_notification.conversation;
+        const conversationStop = event.conversation_stop_notification!.conversation!;
         console.log(`The conversation '${conversationStop.id}' has been stopped.\nThe last message was sent at '${conversationStop.last_received}' on the channel '${conversationStop.active_channel}'`);
         break;
       case 'CONVERSATION_DELETE':
         console.log('\n## CONVERSATION_DELETE');
-        const conversationDelete  = event.conversation_delete_notification.conversation;
+        const conversationDelete  = event.conversation_delete_notification!.conversation!;
         console.log(`The conversation '${conversationDelete.id}' has been deleted.\nThe last message was sent at '${conversationDelete.last_received}' on the channel '${conversationDelete.active_channel}'`);
         break;
       case 'CONTACT_CREATE':
         console.log('\n## CONTACT_CREATE');
-        console.log(`A new contact has been created: '${event.contact_create_notification.contact.display_name}'`);
-        console.log(`List of channels:\n${event.contact_create_notification.contact.channel_identities.map((channelIdentity) => channelIdentity.channel).join('\n')}`);
+        const createNotificationContact = event.contact_create_notification!.contact!;
+        console.log(`A new contact has been created: '${createNotificationContact.display_name}'`);
+        console.log(`List of channels:\n${createNotificationContact.channel_identities?.map((channelIdentity) => channelIdentity.channel).join('\n')}`);
         break;
       case 'CONTACT_DELETE':
         console.log('\n## CONTACT_DELETE');
-        console.log(`A contact has been deleted: '${event.contact_delete_notification.contact.display_name}'`);
+        console.log(`A contact has been deleted: '${event.contact_delete_notification!.contact!.display_name}'`);
         break;
       case 'CONTACT_MERGE':
         console.log('\n## CONTACT_MERGE');
-        const deletedContact = event.contact_merge_notification.deleted_contact;
-        const preservedContact = event.contact_merge_notification.preserved_contact;
+        const mergeNotification = event.contact_merge_notification!
+        const deletedContact = mergeNotification.deleted_contact!;
+        const preservedContact = mergeNotification.preserved_contact!;
         console.log(`The contact ID '${deletedContact.id}' (${deletedContact.display_name}) has been merged into the contact ID '${preservedContact.id}' (${preservedContact.display_name})`);
         break;
       case 'CONTACT_UPDATE':
         console.log('\n## CONTACT_UPDATE');
-        console.log(`A contact has been updated: '${event.contact_update_notification.contact.display_name}'`);
+        console.log(`A contact has been updated: '${event.contact_update_notification!.contact?.display_name}'`);
         break;
       case 'CONTACT_IDENTITIES_DUPLICATION':
         console.log('\n## CONTACT_IDENTITIES_DUPLICATION');
-        const duplicatedEntities = event.duplicated_contact_identities_notification.duplicated_identities;
+        const duplicatedEntities = event.duplicated_contact_identities_notification.duplicated_identities!;
         for(const duplication of duplicatedEntities) {
-          console.log(`The channel ${duplication.channel} contains the following duplicated contact IDs: ${duplication.contact_ids.join(', ')}`);
+          console.log(`The channel ${duplication.channel} contains the following duplicated contact IDs: ${duplication.contact_ids?.join(', ')}`);
         }
         break;
       case 'CAPABILITY':
         console.log('\n## CAPABILITY');
-        const capabilityNotification = event.capability_notification;
+        const capabilityNotification = event.capability_notification!;
         console.log(`Capability for the contact ID '${capabilityNotification.contact_id}':`)
         console.log(`Channel: '${capabilityNotification.channel}' - Identity: ${capabilityNotification.identity}`);
-        if ('reason' in event.capability_notification) {
-          const capabilityUnknownReason = event.capability_notification.reason;
+        if ('reason' in capabilityNotification) {
+          const capabilityUnknownReason = capabilityNotification.reason!;
           console.log(`Reason: ${capabilityUnknownReason.code} (${capabilityUnknownReason.sub_code})`);
           console.log(`Description: ${capabilityUnknownReason.description}`);
         }
         break;
       case 'OPT_IN':
         console.log('\n## OPT_IN')
-        const optIn = event.opt_in_notification;
+        const optIn = event.opt_in_notification!;
         console.log(`Status of the opt-in registration for the identity '${optIn.identity}' on the channel '${optIn.channel}': '${optIn.status}'`);
         break;
       case 'OPT_OUT':
         console.log('\n## OPT_OUT')
-        const optOut = event.opt_out_notification;
+        const optOut = event.opt_out_notification!;
         console.log(`Status of the opt-out registration for the identity '${optOut.identity}' on the channel '${optOut.channel}': '${optOut.status}'`);
         break;
       case 'CHANNEL_EVENT':
         console.log('\n## CHANNEL_EVENT')
-        const channelEvent = event.channel_event_notification;
+        const channelEvent = event.channel_event_notification!;
         console.log(`The event '${channelEvent.channel_event.event_type}' occurred on the channel '${channelEvent.channel_event.channel}'.`);
         if ('additional_data' in channelEvent) {
           console.log(`Additional data:\n${JSON.stringify(channelEvent.additional_data, null, 2)}`);
@@ -202,7 +213,7 @@ export class ConversationService {
         break;
       case 'UNSUPPORTED':
         console.log('\n## UNSUPPORTED')
-        const unsupportedCallback = event.unsupported_callback;
+        const unsupportedCallback = event.unsupported_callback!;
         console.log(`The channel ${unsupportedCallback.channel} has received an unsupported payload:\n${unsupportedCallback.payload}`);
         break;
       default:
diff --git a/examples/webhooks/src/services/voice.service.ts b/examples/webhooks/src/services/voice.service.ts
index 69424f3d..8fe5a518 100644
--- a/examples/webhooks/src/services/voice.service.ts
+++ b/examples/webhooks/src/services/voice.service.ts
@@ -2,7 +2,6 @@ import { Injectable } from '@nestjs/common';
 import { Response } from 'express';
 import {
   aceActionHelper,
-  aceInstructionHelper,
   AceRequest,
   AceSvamletBuilder,
   DiceRequest,
@@ -45,7 +44,7 @@ export class VoiceService {
   }
 
   private handleIceRequest(event: IceRequest, res: Response) {
-    console.log(`ICE request: CLI = ${event.cli} - To = ${event.to.endpoint} (${event.to.type})`)
+    console.log(`ICE request: CLI = ${event.cli} - To = ${event.to?.endpoint} (${event.to?.type})`)
     const iceResponse = new IceSvamletBuilder()
       .setAction(iceActionHelper.hangup())
       .addInstruction(iceInstructionHelper.say('Thank you for calling Sinch! This call will now end.', 'en-US'))
@@ -54,7 +53,7 @@ export class VoiceService {
   }
 
   private handleAceRequest(event: AceRequest, res: Response) {
-    console.log(`ACE request: Call answered at '${event.timestamp.toISOString()}'`);
+    console.log(`ACE request: Call answered at '${event.timestamp?.toISOString()}'`);
     const aceResponse = new AceSvamletBuilder()
       .setAction(aceActionHelper.runMenu({
         barge: true,
@@ -87,7 +86,7 @@ export class VoiceService {
   }
 
   private handleDiceRequest(event: DiceRequest, res: Response) {
-    console.log(`DICE request: Call disconnected at '${event.timestamp.toISOString()}' with the reason '${event.reason}'.`);
+    console.log(`DICE request: Call disconnected at '${event.timestamp?.toISOString()}' with the reason '${event.reason}'.`);
     res.status(200).send();
   }
 
diff --git a/examples/webhooks/tsconfig.json b/examples/webhooks/tsconfig.json
index e43d996c..50c7b919 100644
--- a/examples/webhooks/tsconfig.json
+++ b/examples/webhooks/tsconfig.json
@@ -12,7 +12,7 @@
     "baseUrl": "./",
     "incremental": true,
     "skipLibCheck": true,
-    "strictNullChecks": false,
+    "strictNullChecks": true,
     "noImplicitAny": false,
     "strictBindCallApply": false,
     "forceConsistentCasingInFileNames": false,