Data Gateway and Azure PostgreSQL. Unknown host.

Hi all, 

I am trying to add an Azure PostgreSQL data source in Power BI. The DB is private therefore I have successfully integrated a Data Gateway. In the Manage Gateway settings the 'virtual network data gateway' is "Online" and its data in the 'data sources' is "Online" too. 

Despite all of this, I can't find the data source in the Desktop interface. I then try to add it using the 'Azure Database for PostgreSQL', then, I receive this error:

Details: "An error happened while reading data from the provider: 'No such host is known'"

Sometimes before getting this error the interface asks for credentials but the above error shows after it anyway. 

I've found in some forums references to the Postgresql DB not Azure Postgresql DB which I am not sure is a limitation, is it? . Additionally I am not sure if this feature is just for Premium users (the only error displayed is the unknown host one)

Thanks in advance for your help.