WordPress 5.5 breaks pagination in an older plugin

I finally found a solution.

Disable the redirect canonical function with:

add_filter( 'redirect_canonical', '__return_false' );

And fix the 404 error that results from disabling the redirect canonical with this suggestion

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)