When vlemmy.net disappeared (and it was the only one I had registered to), I registered at lemmy.world, sh.itjust.works, and while I was trying to register at lemmy.ML, I registered at feddit.NL by mistake. (then I requested a login at lemmy.ml, but never got a confirmation).
At the moment feddit.NL is the only instance I have a login at that I can use.
That was a happy mistake :-)
Maybe the problem is me. If feddit.nl goes down, I'll know for sure.
Yes and yes.
You can have multiple communities with the same name in different instances, and not necessarily about the same subject.
You can also have not only the same display name as multiple other users, but even the same username, if not in the same instance.
I did, on feddit.nl, to be able to post this :)
Then I realized the feddit.nl domain was registered less than 2 months ago.
Luckily I don't care about upvote balance (if I did, I'd probably have stayed in reddit as a karma hostage), so I'll just keep hopping instances if they stope working.
Well, not being owned by a profit-driven evil stab-us-in-the-back company going IPO has advantages and disadvantages :-(
It seems dynu.com is a dynamic dns service. Was vlemmy.net running from a variable IP (dhcp) address? Is that usual for lemmy instances?
I signed up for it just a few days ago (reddit refugee), it was working until earlier today.
I've just signed up at feddit.nl now, to be able to post this.
As a funny coincidence, your post showed on my home page 2 posts apart from this one:
https://lemmy.world/post/2021471
(Microsoft forcing migration from the default mail app)