diff --git a/src/Client/BasicAuthClient.php b/src/Client/BasicAuthClient.php
index f778486..371cea5 100644
--- a/src/Client/BasicAuthClient.php
+++ b/src/Client/BasicAuthClient.php
@@ -282,7 +282,7 @@ private function decodeHeaders(string $headers) : array
 
             $headerKey = trim(substr($header, 0, $separator));
             $headerKey = implode('-', array_map('ucfirst', explode('-', $headerKey)));
-            $headerArray[$headerKey] = trim(substr($header, $separator + 1));
+            $headerArray[strtolower($headerKey)] = trim(substr($header, $separator + 1));
         }
 
         return $headerArray;
diff --git a/src/Client/BookboonResponse.php b/src/Client/BookboonResponse.php
index 0301fa9..d0367e7 100644
--- a/src/Client/BookboonResponse.php
+++ b/src/Client/BookboonResponse.php
@@ -58,7 +58,7 @@ public function getHeaders() : array
     public function getReturnArray() : array
     {
         if ($this->getStatus() >= 300) {
-            return ['url' => $this->getHeaders()['Location']];
+            return ['url' => $this->getHeaders()['location']];
         }
 
         $json = json_decode($this->body, true);
diff --git a/src/Client/OauthClient.php b/src/Client/OauthClient.php
index 31b2045..ee9464a 100644
--- a/src/Client/OauthClient.php
+++ b/src/Client/OauthClient.php
@@ -298,7 +298,7 @@ protected function normalizeHeaders(array $headers) : array
     {
         $returnHeaders = [];
         foreach ($headers as $key => $header) {
-            $returnHeaders[$key] = $header[0] ?? $header;
+            $returnHeaders[strtolower($key)] = $header[0] ?? $header;
         }
 
         return $returnHeaders;
diff --git a/tests/Client/BasicAuthClientTest.php b/tests/Client/BasicAuthClientTest.php
index 2479022..2527d37 100644
--- a/tests/Client/BasicAuthClientTest.php
+++ b/tests/Client/BasicAuthClientTest.php
@@ -42,7 +42,7 @@ public function testBadAuthentication()
     public function testNonExistingHeader()
     {
         $headers = "HTTP/1.1 200 OK\n Content-Type: application/json; charset=utf-8\nServer: Microsoft-IIS/8.0";
-        $result = \Helpers::invokeMethod(self::$client, 'getResponseHeader', [[$headers], 'Location']);
+        $result = \Helpers::invokeMethod(self::$client, 'getResponseHeader', [[$headers], 'location']);
 
         $this->assertEmpty($result);
     }
@@ -51,7 +51,7 @@ public function testValidHeader()
     {
         $headers = "HTTP/1.1 200 OK\n Content-Type: application/json; charset=utf-8\nServer: Microsoft-IIS/8.0\nLocation: http://bookboon.com";
         $headerArray = \Helpers::invokeMethod(self::$client, 'decodeHeaders', [$headers]);
-        $result = $headerArray['Location'];
+        $result = $headerArray['location'];
 
         $this->assertEquals('http://bookboon.com', $result);
     }
@@ -81,4 +81,4 @@ public function testNotSupportedMethods($method)
         }
         self::$client->$method($param, "b");
     }
-}
\ No newline at end of file
+}
diff --git a/tests/Client/BookboonResponseTest.php b/tests/Client/BookboonResponseTest.php
index ca3395d..8a5d0aa 100644
--- a/tests/Client/BookboonResponseTest.php
+++ b/tests/Client/BookboonResponseTest.php
@@ -13,7 +13,7 @@ class BookboonResponseTest extends TestCase
 {
     public function testRedirectResponse() {
         $testUrl = 'http://test.com';
-        $bResponse = new BookboonResponse('', 302, ['Location' => $testUrl]);
+        $bResponse = new BookboonResponse('', 302, ['location' => $testUrl]);
 
         $this->assertEquals(['url' => $testUrl], $bResponse->getReturnArray());
     }
diff --git a/tests/Entity/JourneyTest.php b/tests/Entity/JourneyTest.php
index b68979b..6a25589 100644
--- a/tests/Entity/JourneyTest.php
+++ b/tests/Entity/JourneyTest.php
@@ -45,7 +45,7 @@ public function testFirstAllJourneysData()
 
     public function testGetJourney()
     {
-        $data = Journey::get(self::$bookboon, '010e0268-0eec-4859-a67a-ce41ee2315c4')
+        $data = Journey::get(self::$bookboon, '40b8b453-4ce9-425b-baa9-a8d88a589e3d')
             ->getEntityStore()
             ->get()[0];