Error attempting to visit/manage my Wordpress sites: "502 Bad Gateway nginx/1.14.0 (Ubuntu)"

Hello,

I noticed a couple days ago that my wordpress sites were returning this 502 Bad Gateway error (I hadn’t updated in at least several months), and after sifting through a lot of documentation, I don’t think I’m any closer to understanding what the problem is.

Steps I have taken so far:

• upgraded php to 7.3
• tried removing wordpress plugins
• confirmed nginx is running ok
• SSL cert renewal dry run shows OK
• …plus a whole bunch of other trial/error stabs that didn’t help anything

FWIW I have noticed the Apache server fails to start, returning the error: “(98)Address already in use: AH00072: make_sock: could not bind to address [::]:80” though I don’t know if this is even relevant.

I have a single droplet running two wordpress sites on two different domains. These have worked without any problems for at least a few years (migrated over from another hosting service). They are now both returning the same “502 bad gateway” error when I attempt to access them.

Any help would be greatly appreciated, either getting past the bad gateway error, or, if necessary, doing a fresh install of wordpress and my database without losing the existing information.

Thanks, Lcx