PowerBI Dataflows are getting an error with no error message

Hi ucmaoTWG -if you are working on large dataflows (even if only a million rows) can sometimes hit Power BI’s resource or memory limits, especially if the model is complex or if multiple refreshes happen concurrently.

If you’re using a dedicated capacity, make sure it's not overloaded. You can check capacity metrics in the Power BI Admin Portal to monitor CPU usage and memory pressure. If capacity issues are present, consider scaling up or optimizing your data model.

Since you have the Request ID and Activity ID from the error message, these can help Power BI Support troubleshoot more efficiently. If the issue persists, submit a support ticket and provide these details, as they can help pinpoint the cause on Microsoft's end.Ensure that all data sources are still accessible and that credentials haven’t expired. Sometimes, a network change or firewall setting could affect connectivity. 

Hope the above details helps to sort out.