This can be a server crash/bug on the minecraft side. Datapacks do not matter, so do resourcepacks. This is just a bug, we need to wait until it fixes. It also maybe a server update or something like that.
When i try to join minehut, it gives me an error "No valid lobbies found". Pretty self-explanatory i gotta say, BUT. Why is it happening? Why is the online 4000 out of 1700? Can someone explain to me?