Need to use Nginx to create proxy requests for JIRA on a Plesk subdomain

I want to access my JIRA via jira.example.com.

I followed this official instruction; JIRA integration with Nginx

First of all, I configured the connector.

Then, created a subdomain via Plesk, added this additional nginx directive:

location ~ ^ / {
proxy_set_header X-Forwarded-Host $ host;
proxy_set_header X-Forwarded-Server $ host;
proxy_set_header X-Forwarded-For $ proxy_add_x_forwarded_for;
proxy_pass http://127.0.0.1:8080;
client_max_body_size 10M;
}

Then, disable the nginx proxy mode that the proxies request from Apache.

Now; when i go to jira.example.com gives "Oops, you've found a dead link." page of the Jira. This page contains a link to the homepage of the jira, and if I take this route, everything is fine.

In addition, all other things work perfectly.

How can I fix this dead link problem? Thank you.