could it be that they were made by someone from a different instance? so on their end it specified lemmy.world but then resulting in that specification for everyone.
This has happened to a bunch of the communities I created on Lemmyworld. I’ve been trying to ask for help - have created some threads about it and tried DMing the admins - but have never gotten a reply. Not sure what recourse I have, but I get a lot of DMs from users telling me it’s broken.