shows "No Repository" error page in one of the projects

I’ve been having an issue since yesterday when I tried to access one of my projects on It says this:

No repository
The repository for this project does not exist.
This means you can not push code until you create an empty repository or import existing one.

When I try to create a merge request, it allows me to select the available branches. However, when I created, it showed this error:

Whoops, something went wrong on our end.

Please help.