Hello all, I am trying to make a connection with a pre-defined assistant in VAPI to start an audio conversation from a react-native iOS app using client-sdk-react-native. I am sending vapi api key through header and assistant ID through request body but I am getting 400 - Internal server error for the vapiClient.start() call. I am calling the vapiClient method with the following configuration: {"assistantId": "XXXXXXXXXXXXX", "recordingEnabled": true, "transcriber": {"language": "en-US", "model": "nova-2", "provider": "deepgram"}} Any insight on why the start() call is failing? Thanks