Debugging unexpected hangups

• Verify that your AWS Lambda policy grants the lambda:InvokeFunction permission to the voiceconnector.chime.amazonaws.com service principal.

• Check the logs for your AWS Lambda function to ensure that it's being successfully invoked.

• If the logs show incoming events and returned actions, verify that you don't return a hangup action in when the AWS Lambda function is invoked.

• Check the Cloudwatch logs for your SIP media application. The following table lists some of the messages you may encounter.

  Message	Resolution
  AWS Lambda client operation timed out.	The function took longer than 20 seconds to complete. Shorten the response time to less than 20 seconds.
  Access denied while invoking the AWS Lambda function.	The AWS Lambda function doesn't provide a policy that allows the service to access the Amazon Chime SDK Voice Connector service principal. Provide the voiceconnector.chime.amazonaws.com service principal with the lambda:InvokeFunction permission in your AWS Lambda policies.
  The AWS Lambda function was throttled.	The Audio Service couldn't call your AWS Lambda function because the function was throttled. For more information, see https://aws.amazon.com/premiumsupport/knowledge-center/lambda-troubleshoot-throttling/.
  Error while reading actions list.	The PSTN Audio service failed to parse the actions returned by your AWS Lambda function. Check the logs for ACTION_FAILED events, and consult the documentation for the failed action to ensure that you coded it properly.
  The schema version in the invocation request does not match the schema version in the response.	Check your logs and ensure that your request and response use the same schema version.
  Unsupported action name specified	The AWS Lambda function returned an action that the PSTN Audio service didn't recognize. Ensure the action is spelled correctly, and see the documentation for the action.
  Actions list is empty.	The response to a NEW_INCOMING_CALL event didn't return any actions. Return an action in response to that event.
  Too many actions specified in a response.	You returned more than 10 actions in response to an AWS Lambda invocation. Return 10 or fewer actions.
  Response is blank or empty	You returned a null or an empty string. Make sure the response object includes at least the SchemaVersion field.