31486: Busy Here

Twilio returns this when it receives a busy response while trying to connect a Voice call. In Programmable Voice, <Dial> ends the new call when Twilio receives a busy signal, and the resulting DialCallStatus is busy. The Voice iOS and Android SDKs also expose this as Busy Here for call connect and accept flows.

• The called party is already on another call, so the destination returns a busy signal.
• The destination SIP endpoint or carrier network returns a 486 Busy Here response during call setup.
• A <Dial> attempt reaches a busy line, so Twilio exits the dial attempt before connecting the call.

• Use the action URL on <Dial> and check DialCallStatus; when the value is busy, route the caller to voicemail, an alternate number, or a retry flow.
• Retry the call after the destination becomes available. Twilio ends the dial attempt when the line is busy, so a later attempt can succeed.
• Verify the destination number or SIP endpoint is correct and ready to receive calls before you place the call.

• Error and Warning Dictionary
• TwiML Voice: <Dial>
• Voice SDK Error Codes