'install wordpress' when trying to login

Hello people,

For the past few days i have been having a small problem.this happened last saturday but then it stopped by sunday until it came back today.

when trying to log into my admin and also when trying to view my site a page shows up telling me to install wordpress.

my site link turns to:
https://www.circusmalta.com/wp-admin/install.php

my other 2 sites do not have this problem.

(it is hosted on a server)

Any info please?

Thanks, Alan