Login Not Working - Nothing Happens After "Login"

Hello guys,
For some reason, I am not able to login to the wordpress site.
When I click to login, the data is erased and nothing happens. If I enter wrong user and password, there ir no error. It literally just resets the login form.
I tried changing the plugin directory name, but issue still there.
Also, I use ManageWp and I am able to login from there.
Any ideas what could be going on?