If it's only been a day, I might wait a bit longer before writing it off. The issue could very well be resolved soon. Even the big tech companies have a service go through problems for a day or two.

I only tested Notesnook for a few days, so I may not remember it's key elements well, but Standard Notes seemed like a very similar product (the downside is the subscription, it was basically unusable to me without paying).

The NotesNook UI is the best I've seen, it's hard to find that level of polish in a FOSS android app.

I think you'll struggle to find what you're looking for without a subscription model unfortunately. If you do want to retry Joplin that is my recommendation, I run it with a locally hosted Joplin sync server, it's fantastic for my use case. It's been recieving a lot of solid updates lately too.