I have the same problem, and if a go to Morgana theres not option to leave.
Viewing post in Corrupted Kingdoms (NSFW 18+) comments
Did you check if there's an exit icon on the bottom right?
Honestly, I still think Arc should've kept both the button and the menu option.
If there is no exit button or a menu option, something may have gone terribly wrong.
And frankly, diagnosing the issue through here is a mess, try joining the discord.