I tried to sync my discord to my mc account/play uhc because that is what it said for existing members to do as well as new members. Once I did it now is fully desycned like I can't access any chats and no matter what I try I can't access the discord server properly. I tried doing the process over and over and it is not working.
Leave the Discord server first. Then go to the hub, do the /discordsync command, and a message in the server chat will tell you to click the message and use that invite link to join the Discord server.