diff --git a/app/celery/tasks.py b/app/celery/tasks.py
index 720bed74d..8ee59a00a 100644
--- a/app/celery/tasks.py
+++ b/app/celery/tasks.py
@@ -320,7 +320,7 @@ def send_sms_code(encrypted_verification):
         mmg_client.send_sms(validate_and_format_phone_number(verification_message['to']),
                             verification_message['secret_code'],
                             'send-sms-code')
-    except Exception as e:
+    except MMGClientException as e:
         current_app.logger.exception(e)
 
 
diff --git a/app/clients/sms/mmg.py b/app/clients/sms/mmg.py
index 9efffee88..687696055 100644
--- a/app/clients/sms/mmg.py
+++ b/app/clients/sms/mmg.py
@@ -52,16 +52,20 @@ class MMGClient(SmsClient):
             "reqType": "BULK",
             "MSISDN": to,
             "msg": content,
-            "sender": self.from_number
+            "sender": self.from_number,
+            "cid": reference
         }
 
         start_time = monotonic()
         try:
+            import json
             response = request("POST", "https://www.mmgrp.co.uk/API/json/api.php",
-                               data=data)
+                               data=json.dumps(data),
+                               headers={'Content-Type': 'application/json',
+                                        'Authorization': 'Basic {}'.format(self.api_key)})
             if response.status_code != 200:
-                error = response.json
-                raise MMGClientException(error)
+                error = response.text
+                raise MMGClientException(json.loads(error))
             response.raise_for_status()
         except RequestException as e:
             api_error = HTTPError.create(e)