Long story short: I messed up with the domain registration for this instance, and never replied to a mandatory email. The domainname (lemmit.online) got put in suspension, causing disconnects all over the fediverse.
I fixed it as soon as I found out, but it will probably take a few more hours for the issues to be fully fixed.
So ehm. Whoops. Hope this explains and fixes the federation issues we’ve been having today.
Unknown. I’d first need to setup a local test instance to assure it works. Up until now I’ve been testing my bot against production (YOLO!)