Why does this config cause persistent SIP trunk registration failures when deployed through our AppFoundry integration?
We are currently finalizing the deployment of a custom telephony integration that bridges Genesys Cloud with a legacy PBX system. The application is built as a Premium App within the AppFoundry marketplace, designed to handle SIP trunk provisioning automatically for new tenant onboarding. The integration uses the standard OAuth 2.0 client credentials flow to obtain access tokens for the Platform API. The service account has been granted the telephony:trunk:write and telephony:trunk:read permissions, which aligns with the documentation for managing SIP trunks programmatically.
The issue arises during the POST /api/v2/telephony/sip/trunks endpoint call. When the application attempts to register a new SIP trunk with a specific codec negotiation setting, the API returns a 403 Forbidden error. The error payload indicates: “Insufficient permissions to modify advanced SIP settings for this organization tier.” This is unexpected because the target organization is a full Enterprise Plus license, which should support all SIP trunk configurations. Furthermore, manual configuration of the exact same SIP trunk settings via the Genesys Cloud Admin UI succeeds without any issues. The service account is linked to the correct organization ID, and the OAuth token is valid at the time of the request, verified via token introspection.
We have tested this across three different tenant environments, all resulting in the same 403 response. The request headers include the correct Authorization Bearer token and Content-Type application/json. The body contains the trunk configuration JSON, including the sip_settings object with explicit codec preferences. Disabling the advanced codec settings allows the trunk to be created, but this breaks our compatibility requirements with the legacy PBX. We are running this integration from AWS us-west-2, and the Genesys Cloud instances are also in the us-east-1 region, so latency is not a factor. Any insights into why the API enforces this restriction despite the correct role assignments would be appreciated.