403 Authorization Failed — NVIDIA NIM API Chat Completions

Hello NVIDIA Support Team,

I am developing a personal AI assistant using the NVIDIA NIM API and Python.

My API key is loaded correctly, and GET /v1/models works successfully. However, POST /v1/chat/completions returns:

403 Forbidden — Authorization failed.

I have regenerated my API key, completed my NVIDIA Developer profile, and confirmed that the issue persists.

Model: nvidia/nemotron-3.5-lightning-30b-a3b

Could you please check whether my account has access to hosted inference and Public API Endpoints?

Thank you.