Site on Hosting not working at all: Error 504 - Gateway Timeout

Hi, I have been away for a week and I now notice that the test site I put on the hosting platform is not working. I haven't done anything to it so it must be an issue on your end. It returns:
"Error 504 - Gateway Timeout"

Basically I can't do anything with this site. I can't access the database from the hosting panel - I can't access the site admin or site and I can not restore a backup ether - it is as if the site has vanished?
I basically installed it on the 5th feb and it was running till the 13th. I didn't do anything to it and have been away for the past week and now I can't access it (last backup was on the 14th feb).

Have you guys made changes to the Hosting settings that may have affected the site?