502 Bad Gateway nginx

Hello,

Since I installed a plugin on my Wordpress site, I ran into a 502 Bad Gateway error.
Also, my other Wordpress installation on another domain shows the same error, even though they are not multisite installations.
It seems like there is nothing I can do on my site and have to wait until someone at the helpdesk sorts this out.
Nevertheless, can I do something myself to deblock my site?

Thank you