Function App: Troubleshooting 403 Forbidden on Test/Run and Admin Path Access

Problem description

I am experiencing a 403 Forbidden error when attempting to test my Function App via the Azure portal Test/Run feature. The logs are empty, and the request does not reach my function code. I suspect there might be an authorization or permission issue before the function execution begins.

Environment

Function App, Azure portal, Region not specified in case information.

What I've already tried

I have added the Azure portal origins to the Function App CORS allowed origins list and confirmed the settings are saved. I also tried calling the admin endpoint directly using the current host keys via curl, but the 403 Forbidden response persists. I have ensured that public network access is enabled, and no access restriction rules are configured.

Current status

The issue appears to be an authorization problem before the function code runs, possibly at the portal or admin path level. I am seeking guidance on how to diagnose and resolve the 403 Forbidden error during the portal Test/Run invocation to allow proper testing of my PowerShell function.