Read this on resetera:

[I never played an AC before New Horizons came out so I bought the game during the Pandemic and after a few month of paying, I put it on the shelf and forgot about it.

My island was crappy. No much going on beside I spent most of my time growing all types of flowers and collecting fossils. Never bothered with the updates and DLCs until the Switch 2 version came out.

Since it was free for Nintendo Online Members I decided to do the hotel dlc which I did in a week. After that I went to the Happy Home Paradise DLC and couldn't stop making vacation homes and facilities since I now have a lot of to play with, unlike my island which I didn't have much DIY recipes in my catalog.

Now I can't stop!! Every night I will travel to treasure islands and grab a bunch of DIY recipes, furniture, materials, etc for my island. Now I'm in the process of completely re-arranging my island with customs path designs I have been grabbing and watching videos from YouTube about island design tips.]

Lol

My problem is that lost several Nintendo accounts for fake people I used to own more houses in Animal Crossing. Now I have 4 houses where I cant actually mess with anymore.

And if I delete the user on Animal Crossing itself, I lose the whole house and all items.