Hi @Andre_Rodrigues ,
Please try to go to the refresh settings for a dataset. In "Manage Data Sources", for any data source with an error, select "Edit credentials". Then sign in to the data source again.
You could reference the following document to check the issue of your gateway.
Troubleshooting Power BI gateway (personal mode) - Power BI | Microsoft Learn
Troubleshoot gateways - Power BI | Microsoft Learn
Community Support Team _ xiaosun
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