Trouble connecting to communities at lemmy.ml

I'm trying to transfer my subscriptions from lemmy.ml over to a new account here, but the community search is failing to find most of those subs. For example: comics, esp32, selfhost, and datahoarder.

Even if I try reaching the url directly (https://mander.xyz/c/homeserver@lemmy.ml) I get a "404: couldnt_find_community" error. Are these communities blocked from Mander for some reason?