I tested moving campaigns to a folder in my account and was able to move the campaigns. Can you tell me more about what you are doing when you are moving campaigns? Are you selecting one campaign or multiple campaigns, if so how many? Have you tested in a different browser to see if you get a different result? Also, which browser are you currently using when you are accessing your account?
The term MOVE is incorrect.
They aren't really moved, they are copied.
They will remain in the ALL listing with a note indicating where else they are. See attached: