Power BI reports do not refresh in Power BI Embedded service even after setting all credentials to p

Hello community,

Since a couple of weeks we are having problems with the scheduled refresh in Power BI. I will make you a quick recap of the things we tried:

1. Our purpose is to show the Power BI reports in a WebAapp. In our company we create "Projects" for our clients and based on that a Power BI report is taken from a template -- updated with the project code (which is a parameter in the .pbix template file) -- uploaded to https://app.powerbi.com/groups/whateverclientid and then scheduled to be refreshed every X hours. The credentials are set in the C# WebApp backend we have, before it is uploaded to the Power BI Service. That way each client only is capable of accessing their own data, and nothing more. There is no way to overexpose/leak data from the frontend.

2. We were doing this until we encounter a new situation: now we have to pull data not from 1 storage account but from 2 and there is no way to overload the .NET function we need for setting the credentials in the backend.

3. Therefore, since the Power BI data itself is unaccessible from the frontend anyway we decided to set the credentials in the template itself, changing them to public and simply change the project code parameter in the frontend. This way all the credentials are already saved by default from the template and it is just a matter of refreshing the report once we upload it to https://app.powerbi.com/groups/

4. This was working perfectly until 2 weeks ago. We suddenly saw that the reports stopped refreshing with the scheduled refresh. If we take over/download the report and try to refresh it manually it works perfectly (so the credentials are correct).

So, we do not understand why it is suddenly not working, while it was indeed working around a month ago. Does anyone have any idea or has experienced the same issue?