diff --git a/artshow/manage.py b/artshow/manage.py
index 386567e..b3f2c12 100644
--- a/artshow/manage.py
+++ b/artshow/manage.py
@@ -350,8 +350,8 @@ def make_payment(request, artist_id):
             artist,
             f'Art Show space reservation for {artist}',
             payment_remaining,
-            request.build_absolute_uri(reverse('artshow-manage-payment-square',
-                                               args=(artist_id,))),
+            settings.SITE_ROOT_URL + reverse('artshow-manage-payment-square',
+                                             args=(artist_id,)),
         )
         if payment_url is not None:
             return redirect(payment_url)
diff --git a/artshow/square.py b/artshow/square.py
index f9bb0df..8092940 100644
--- a/artshow/square.py
+++ b/artshow/square.py
@@ -5,6 +5,7 @@
 from decimal import Decimal
 
 from django.http import HttpResponse
+from django.urls import reverse
 from django.utils.timezone import now
 from django.views.decorators.csrf import csrf_exempt
 
@@ -72,11 +73,14 @@ def process_payment_created_or_updated(body):
     payment_id = payment['id']
     payment_amount = Decimal(payment['total_money']['amount'] / 100)
 
-    square_payment = SquarePayment.objects.get(order_id=order_id)
-    square_payment.amount = payment_amount
-    square_payment.payment_type_id = settings.ARTSHOW_PAYMENT_RECEIVED_PK
-    square_payment.payment_id = payment_id
-    square_payment.save()
+    try:
+        square_payment = SquarePayment.objects.get(order_id=order_id)
+        square_payment.amount = payment_amount
+        square_payment.payment_type_id = settings.ARTSHOW_PAYMENT_RECEIVED_PK
+        square_payment.payment_id = payment_id
+        square_payment.save()
+    except SquarePayment.DoesNotExist:
+        logger.info(f'Got webhook for unknown order: {order_id}')
 
 
 def process_webhook(body):
@@ -91,7 +95,7 @@ def webhook(request):
         body,
         request.headers['x-square-hmacsha256-signature'],
         settings.ARTSHOW_SQUARE_SIGNATURE_KEY,
-        settings.ARTSHOW_SQUARE_NOTIFICATION_URL)
+        settings.SITE_ROOT_URL + reverse('square-webhook'))
 
     if not valid:
         logger.debug('Received invalid webhook!')
diff --git a/artshowjockey/settings.py b/artshowjockey/settings.py
index 30a0d9c..bdd6ece 100644
--- a/artshowjockey/settings.py
+++ b/artshowjockey/settings.py
@@ -263,7 +263,6 @@
     ARTSHOW_SQUARE_ACCESS_TOKEN = env.str('ACCESS_TOKEN', default='')
     ARTSHOW_SQUARE_SIGNATURE_KEY = env.str('SIGNATURE_KEY', default='')
     ARTSHOW_SQUARE_ENVIRONMENT = env.str('ENVIRONMENT', default='sandbox')
-    ARTSHOW_SQUARE_NOTIFICATION_URL = env.str('NOTIFICATION_URL', default='')
 
 SITE_ID = 1
 SITE_NAME = ARTSHOW_SHOW_NAME