Dashboard appearing in plain HTML and all backend links giving 404 Error

My website is currently using wordpress version 6.0. When I try to open the dashboard, it appears in plain html.
Also, when I try to open any tab from the backend like pages, posts, permalinks, plugins etc. it gives 404 error. However, the front-end seems to be working absolutely fine.

Going through forums, I found a solution which was adding the below lines of code into config.php

define('FORCE_SSL_LOGIN', true);
define('FORCE_SSL_ADMIN', true);
define( 'CONCATENATE_SCRIPTS', false );
define( 'SCRIPT_DEBUG', true );

Now, this brings my dashboard into proper format but does not resolve 404 error, when trying to access, permalinks, all posts, all pages or other settings from the dashboard.

I need to launch the website at the earliest. Any help would be appreciated.

• This topic was modified 2 years, 9 months ago by Jan Dembowski. Reason: Moved to Fixing WordPress, this is not an Everything else WordPress topic

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