Twilio WebRTC Expert Needed to Fix TURN/ICE Connectivity & Voice Call Failures

We are experiencing Twilio Voice/WebRTC connectivity issues in our browser-based calling application. Twilio diagnostics show that TURN UDP connectivity is failing, while TURN TCP and TLS connectivity pass. Voice test calls fail with Error 31009 (“No transport available to send or receive messages”) and ICE connection establishment failures. We need an experienced Twilio/WebRTC specialist to diagnose the root cause, determine whether the issue is related to network/firewall settings, TURN/STUN configuration, ICE negotiation, or Twilio Voice SDK implementation, and implement a working solution. The goal is to restore successful browser-based voice calls and document the fix.