Issue Lets Encrypt - error in certificate renew process

[netbuild]

Nobody has claimed that. It doesn't help to make accusations here.
Why would anyone want to do that?
You already mentioned that.

This is how it looks on my private server, but on all other 50 Plesk servers too

    location ^~ /.well-known/acme-challenge/ {
        root /var/www/vhosts/default/htdocs;

        types { }
        default_type text/plain;

        satisfy any;
        auth_basic off;
        allow all;

        location ~ ^/\.well-known/acme-challenge.*/\. {
            deny all;
        }
    }

You could check whether the route for http traffic is the same as for https traffic.

is exactly the same route

Are you using a proxy like Cloudflare? Could the issue be linked to port-related setting there?

We don't use that and no

Do you have any individual Nginx or Apache configuration directives in effect in your domain ("Apache and Nginx Settings")? These could take precedence over the default 301 in the "server" bracket of nginx.conf of the domain.

no, no individual settings have been made here

 

[Peter Debik]

If you cannot find out where a redirect is done with the requirement of a working certificate, the best option will be to submit a support ticket to Plesk support so that an engineer can check it on your server why this happens.

i couldnt find anyone who could post a successful automatic lets encrypt renewal.

@t.echternach-weber The normal behavior is that certificates can be renewed without issues, with or without SSL redirect "on".