azure endpoint filestream

Question

Hello. I posted 2 apis on my Azure cloud, and both are accessible via the app url. The first one displays the API data as normal. But the second api I have setup to auto-filestream files to the user and it currently is failing with a 500 server error. Locally this filestream works just fine (it basically filestreams as a PDF file), but once I load my API to Azure as containerized app, then it gives me that error. What do I need to do to get this working, is this a matter of security config or something more?