Unable to add new connection to data gateway except the localhost connection

Hi,

I am trying to use PowerBI with a PostgreSQL database, and I was sucessfully develop my report with 

- PowerBI Desktop on my Local Machine

- On-premise Data Gateway on my Local Machine

- PostgreSQL database on my Local Machine

After I published the report to PowerBI, the data gateway on my Local Machine show up and I can get data and the report works perfectly.

The problem is that, now when moving this to production, I have my PostgreSQL database on a machine A and my data gateway on machine B. I have tested the database connection from machine B to machine A using a separate SQL client and it works perfectly, but when I added this connection on power BI online, it keeps showing up that my production data gateway is "not configured properly"

Please check out my above picture, the top one is my local data gateway with local postgres and it works just fine.

The bottom one is the production data gateway and production postgres, on two separate machines. No matter how I do the "Add To Gateway" configuration, the connection does not show up there for mapping.

Thank you very much in advance