Hello,

I would recommend checking if your Wordpress default .htaccess file rules are present. This is a very common cause of that problem.

Also make sure that you have mod_rewrite enabled:

sudo a2enmod rewrite

And then restart Apache:

systemctl restart apache2

Finally, if this does not help, I would recommend following the steps here on how to troubleshoot common Apache problems:

https://www.digitalocean.com/community/questions/how-to-troubleshoot-common-apache-issues-on-linux-server

Regards,
Bobby