Gateway Connection Problem

Hi, Evans_Santos 

Check your firewall settings to make sure that there are no firewall rules blocking the connection between the Power BI gateway and the PostgreSQL database. Sometimes, the firewall may drop packets which leads to this error. 
You can try increasing the timeout setting in the Power BI connection string. You can check the following post:

Solved: Postgresql: Exception while reading from stream - Microsoft Fabric Community

Install the npgsql provider to ensure that the npgsql provider is installed on the server that hosts the data gateway. This is required for the PostgreSQL connection to work properly. You can refer to the following post:

Solved: Configure Gateway to connect to PostgreSQL - Microsoft Fabric Community

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Best Regards

Yongkang Hua

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