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  • I was using the TwilioClient 1.2 SDK and just migrated to the Programmable Voice SDK. Why am I getting “Authentication error” using my Capability Token?
    • The Programmable Voice SDK requires a new token format called the Twilio Access Token for authentication. Please update your token vending endpoint to generate Access Tokens for your application.
  • I’ve created an Access Token vending endpoint but why do I keep failing to register for incoming call push notifications?
    • Twilio Access Token supports authentication for multiple products, but you need to make sure that you are using VoiceGrant for the Programmable Voice SDK.
    • You might have used the incorrect API key/secret pair to create the Access Token. Please make sure you keep the API secret privately once the API key is created, and use both the API key and secret to create the Access Token.
    • The maximum expiry duration allowed by Twilio is 24 hours, which equals to 86400 seconds. Please make sure that you have expiry <= (86400 -1).
    • The API keys/secrets are not sharable between main account and sub-accounts.
    • Please make sure the Access Token has non-empty identity.
  • Why am I not receiving any incoming call push notification although the SDK says it registered successfully?
    • The Twilio Programmable Voice Android SDK requires FCM SECRET or FCM Server Key to be able to send push notifications to signal arrival of an incoming call. You need to use these values to create a Push Credential. If the google-services.json used in your application is not the correct one associated with the FCM SECRET or FCM Server Key, notification will fail.
  • Make sure you do not exceed more than 10 active registrations for the same identity. Twilio will notify only most recent 10 registered device and the rest of the devices will not receive notification.

Outbound Call

  • Why am I not able to make calls even though I am using Access Token?
    • Make sure you are using a valid Account SID, a valid API signing key and a valid secret in the Access Token.

Great tools and links

How to file a support ticket or create a Github issue

We love feedback and questions especially those with helpful debugging information so we can diagnose and respond in time. When submitting issues or support tickets, it would be great if you add the following:

  • Description - what are you trying to achieve, what steps did you take, and what issue did you have.
  • SDK version
  • SDK verbose log - SDK logs are always the best for the team to debug. Configure the SDK log level, and set it to DEBUG: Voice.setLogLevel(LogLevel.DEBUG)
  • Twilio account SID
  • Twilio call SID

When you have gathered all this helpful information, please file any issues you find here on Github.

For general inquiries related to the Voice SDK you can file a support ticket.

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