Product: Programmable Voice
The WebSocket protocol handshake was declined by the server The server has returned an HTTP code different from 101 to the connection request sent by stream
See https://tools.ietf.org/html/rfc6455#section-4 for details.
- The server does not support WebSocket
- The WebSocket protocol is not enabled for the requested URL
- Verify WebSocket protocol is enabled in the server
- Verify the path in TwiML URL is actually the one supporting WebSocket