I have some old subscriber groups, from a since deleted campaign, which i want to delete. Everytime i try, it sends me to a 404 page. I have tried this in Chrome (incognito as well) and Edge. I suspect it has to do with the fact that since the old campaign doesn't exist anymore, it's trying to refer to that campaign whilst trying to delete the group.
I'm not sure if these steps are reliable, since i encountered the bug probably a while after it was there.
Is the subscriber group empty of users?
Any Updates on this? I'm also encountering this issue.