13231: Dial->Conference: Invalid endConferenceOnExit value

Twilio returns this error when your <Dial><Conference> TwiML sets endConferenceOnExit to a value other than true or false. Use this attribute to control whether the conference ends when that participant leaves. If you omit the attribute, the default value is false.

• Your application sends a value such as True, FALSE, yes, 1, or another non-boolean string for endConferenceOnExit.
• Your TwiML template or helper library inserts extra quotes, whitespace, or other invalid characters into the endConferenceOnExit attribute. This causes the final <Conference> noun to contain a value Twilio cannot parse as true or false.
• Your application maps user input or configuration values directly into endConferenceOnExit without validating them first.

• Set endConferenceOnExit to true or false only. For example, use <Conference endConferenceOnExit="true"> or <Conference endConferenceOnExit="false">.
• If you do not need the conference to end when that participant exits, remove the endConferenceOnExit attribute and let Twilio use the default value of false.
• Validate the generated TwiML before you return it to Twilio. Confirm that the final XML contains a valid <Conference> noun and that endConferenceOnExit is set to a supported boolean value.
• If your application builds conference participants dynamically, normalize configuration values before rendering TwiML so only true or false is passed into the attribute.

• TwiML <Conference> noun
• TwiML <Dial> verb
• Conference Participants resource