Database not showing up

I have a proble mwith the deployment server connection. When I try to setup a new database connection the database list does not open up. It remains blank, no Error. I tried this on my NAS server, on XAMPP and on my raspberry-PI LAMP server. Same result. Usually when the credentials or IP/port are wrong there is an Error showing up. Tried different browsers - nothing

Your database is not Local? If yes then you must have permission for external conections.

THANK YOU FOR REPLYING.

If am running XAMPP on another Windows machine and just decided to reinstall XAMPP and this helped. Looks like some files got corrupted.
Now into testing this on another computer. This time RASBERRY-PI running LAMP server.