Refresh Failed: DMTS_OAuthTokenRefreshFailedError

Hi, WesleyvB 

I am glad to help you.   

According to your description, you are mainly trying to solve the problem of data source connection failure which leads to refresh failure? 

If I understand you correctly, then you can refer to my solution.  

First, you can open the corresponding .pbix file in Power BI Desktop, and then click Edit Permission to modify the Privacy Level. Sometimes Privacy Level can also affect the data source connection error. 

You can also check whether the corresponding gateway you are using is working properly. If the gateway is offline, log in.  

If it is working, you can try to update the credentials: 

And you can also check if your gateway version is at the latest version. If not you can update to the latest version: 

I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.
Best Regards,
Fen Ling,
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