Trying the mentioned code with registeration_ids and to parameter and both are not working. Help me to solve the same. Every time it is giving this error of multi cast id and InvalidRegistration. Getting this error: {“multicast_id”:8367359766XXXXXXXXX,”success”:0,”failure”:1,”canonical_ids”:0,”results”:[{“error”:”InvalidRegistration”}]} Answer Invalid Registrations usually have one of the following reasons: The registration token/device token is invalid The client app has actively unregistered with