13338: Gather: Invalid actionOnEmptyResult value

This error occurs when <Gather> receives an invalid or empty actionOnEmptyResult value. Set actionOnEmptyResult to true or false; the default is false.

• actionOnEmptyResult is missing from the <Gather> attributes.
• actionOnEmptyResult is set to a value other than true or false.

• Set actionOnEmptyResult to true or false in your <Gather> verb.
• Use true when you want <Gather> to send a webhook even if the caller provides no input.
• Leave actionOnEmptyResult at its default false value when you want the call flow to continue to the next TwiML instruction after an empty gather.

• TwiML Voice: <Gather>