The Genesys Cloud Outbound API is returning HTTP 403 Forbidden when JMeter 5.6 attempts to start a campaign via POST /api/v2/outbound/campaigns/{id}/start.
This happens only when simulating high concurrency. A single request works fine. But at 50 concurrent threads, the 403 errors appear.
The environment is Genesys Cloud US1. The JMeter test uses valid admin credentials with full outbound permissions.
The error response body is generic.
{
“message”: “Forbidden”,
“status”: 403
}
No specific rate limit header is returned. The 429 status code is not used here. It is strictly a 403.
I checked the user permissions again. The role has outbound:campaign:write and outbound:campaign:start.
Is there a hidden concurrent start limit for campaigns? Or is this a validation error masked as a 403?
The load test aims to validate system stability under bursty start conditions. We need to know if this is a configuration issue or a platform limit.
Any insights on troubleshooting this specific 403 behavior would be helpful.