Yeah, if you were actually in this situation, that isn’t something you’d just forget, unless your intelligence is extremely low (low enough that you probably wouldn’t have the idea to use the rope in the first place). This is bad DMing. They should have said something like: “You’re aware no one is holding the rope. Are you sure?” If that’s actually what they wanted to do, they can do it. If not, they are now aware.
Yeah, if you were actually in this situation, that isn’t something you’d just forget, unless your intelligence is extremely low (low enough that you probably wouldn’t have the idea to use the rope in the first place). This is bad DMing. They should have said something like: “You’re aware no one is holding the rope. Are you sure?” If that’s actually what they wanted to do, they can do it. If not, they are now aware.
If you REALLY want shenanigans, have them make an int or wis saving throw with DC 2 to remember nobody is up there holding the rope.