This error may be normal game bugs, There was one recently that affected anyone who went to the Muggle studies classroom, if after closing the app and trying to solve it, it was not solved, send a message to game support describing the problem (If you send a screenshot, hide the icon of the mod, so that you avoid banning)
Ah sorry, I misunderstood a bit.
Try to close & lauch the game again. It'll force to reopen the quest, maybe there will be more objects shown.
Otherwise I'm afraid you can only wait for the entire time.