Thanks — I’m looking into the "Error creating SIP participant: ... 403: Forbidden" you're seeing. That 403 means the SIP provider rejected the INVITE (authentication/authorization issue). To help quickly, could you share the following: • Which SIP provider are you using? • Are you authenticating with username/password or by IP whitelisting? • The SIP trunk configuration (fields like

auth_username

,

auth_password

, allowed IPs, and

sip_number

/ caller ID) — redact secrets if needed. • Any provider-side logs or the full INVITE/403 response (if available). • Whether your LiveKit server IP is whitelisted with the provider and the transport (UDP/TCP/TLS) you’re using. If you prefer, tell me one thing you want me to check first (credentials, IP whitelist, caller ID, or transport/certificate). I’ll guide you through the next steps. Sources: livekit/livekit_sip.twirp.go | sip | livekit/livekit_composite | DeepWiki | Understanding TLS in SIP | LiveKit | Understanding TLS in SIP | LiveKit | Preserving Caller ID During SIP Transfers in LiveKit Agents, with interactive elements