Hello lucke-stz,
Have you added any plugin recently? Isn’t that plugin is causing conflicts? Please check once by deactivating the recently installed and activated plugin once.
Let us know the results.
Thank you
First I tried to deactivate all plugins and the problem persists. So I found a post on internet telling about .htaccess file. I edited the .hatacess file to standard configuration and the problem was solved! 😀
Hope this can help more people with the same issue.