- Environment: Genesys Cloud EU1, Zendesk Talk legacy, SIP Trunk v2
- Status: 403 Forbidden on INVITE
Trying to understand why the SIP trunk returns a 403 Forbidden when routing inbound calls from our legacy Zendesk Talk PSTN provider. In Zendesk, the DID mapping was static and simple. Here, the Genesys Cloud SIP trunk configuration seems to reject the SIP headers. The error log shows 403 Forbidden: Authentication Failed despite correct credentials. Is there a specific header requirement or TLS mismatch causing this drift?