Okay, so I will wait for the maintenance to see if my problem got resolved. In addition, FYI, I have just met a similar issue regarding to the frequent disconnection (3 times in a row within a couple minus) from the server with error code 90002 in a primal fighting instance. After reconnecting and logged on to the server, I got stuck at loading screen as well. It makes the game unplayable sometimes.
The pattern is like:
disconnected with error 90002 => re-logon (very smooth, my char didn't hold on the server) and stuck at loading screen (at least 2mins) => back to normal (I can control my char and play the game in 1-2 minuses) => disconnected with error 90002 (repeat until I got dismissed and return to the open world)

I hope this information could help. Thanks for your attention.