I know what you mean. The biggest issue I'm having is finding and subscribing to communities that are not a part of the instance I joined with.
I kept seeing links that listed communities I was interested in subscribing to, but then it would ask me to log in, I'd put in my credentials, only for the log in to not work. I finally realized I had to make a new account with that instance, and then i could log in and join it. I don't want to have to juggle between 3 or 4 accounts to enjoy content, plus much if it is duplicated as some instance are linked, but others are not.
Also I use Jerboa to browse lemmy, don't have a PC, and would rather use an app than my web browser(Brave).
Just tried it from my lemmy.fmhl.ml account, the account I initially made, and wasn't able to locate !Washington@lemmy.world
It might just be an issue with Jerboa.