504 Gateway Time-out OR Database Connection Error

I registered yesterday. I want to make wordpress website (school project ):
After multiple tries i succeed in installation. ( a lot of errors).
And yesterday and today it keeps showing these two errors when I try to log in.
Do you know why ?

What is your website address and what scripts are you running now?

It is just installed. I didn’t do anything to it yet. It let me log in for few times, but very hard.

it is freshly installed, there is nothing on it yet.
Sometimes it let me log in, but mostly not.

Loading fine now check status.000webhost.com next time your site won’t load.