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51123: Twilsock: Upstream not resolved


ERROR: 51123

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ERROR

Twilsock could not resolve the upstream target specified in the request. This error usually indicates that the upstream identifier is missing, malformed, or references a destination that is not available for the current Twilio client connection.

Possible causes

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  • The request includes an invalid upstream identifier.
  • The upstream value is missing or formatted incorrectly.
  • The client is attempting to connect to an upstream target that does not exist.
  • The upstream target is not available for the current service configuration or environment.
  • The SDK or application is passing the wrong parameter value when opening or routing the connection.
  • Verify that your application sends a valid upstream value in the request.
  • Check your client configuration and confirm that all required connection parameters are present and correctly formatted.
  • Make sure the upstream target exists in the environment your application is using.
  • Review recent application changes that affect Twilio client initialization, connection setup, or routing logic.
  • Update to the latest supported Twilio SDK version if you are using an older client implementation.
  • If the error persists, enable SDK logging in your application and review the request details sent during connection setup.

Additional resources

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