403 Forbidden Error in webui

HI! First, I'm very sorry if this is the wrong community, if there's a better comm, please point me in their direction.

I've been running my own piefed instance for a few months now, but recently (maybe? idk how long this has been happening), if I try to open the webui from a private browser tab, or from another device, I get a 403 forbidden error code. {"code":403,"status":"Forbidden"}. Is this a common issue?

I've been trying to look this up online and it seems like it might be nginx, but I have many other things running behind nginx with that don't act like this, so I figured I'd ask here before going to a more general nginx community.

You're more than welcome to try going to my instance yourself, at piefed.zeromedia.vip

UPDATE:

Turning the "private instance" setting on and then back off seems to have fixed it. I'm not 100% yet but I can currently access piefed on all devices/browser sessions

Update 2:

That didn't quite fix it, for some reason, turning the private instance setting on does fix it, but as soon as I turn it off again, it breaks