Failed to update data source credentials for postgreSQL server in PowerBI Service

Hi Anonymous 

If your PostgreSQL is not hosted in a cloud environment which allows direct connection from the Power BI services, you'll need to use an on-premises data gateway for refreshing data from the Power BI Service. Please see Prerequisites section from Power Query PostgreSQL connector - Power Query | Microsoft Learn

In your scenario, you probably need to use an on-premises data gateway. Once you have installed and configured a gateway, you need to add the PostgreSQL data source to that gateway. The crendentials to access the PostgreSQL data source is configured when adding the data source. Then after you publish a report to the Power BI Service, you can go to its settings page and select that gateway for refreshing the semantic model which is used in the report. 

On-premises data gateway - Power BI | Microsoft Learn

If you are not familiar with the on-premises data gateway, you may find the following blog helps a lot!

The Power BI Gateway; All You Need to Know - RADACAD

Best Regards,
Jing
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