Power BI Dashboard not refreshed

[uzmaali]

We are using Power BI Reporting Service (in-premise) version 1.5.7074.36177 (May 2019) and have recently encountered an issue with the Power BI dashboard reports hosted on the reporting server.

We have noticed a few times on an ad-hoc basis that the Power BI Report Server schedule is working without errors, but the data within the dashboard is not updated. If we open the Power BI Desktop file, there are data errors in the Edit Query similar to below which get resolved on selecting Refresh All. After pressing save, then the data does get updated.

Is there a way to see in the SSRS Log for such errors? Has anyone experienced similar issue?