
Continuity mistake: Just before Flynn cuts off Rapunzel's hair, there is a shot from behind him and he reaches up with his right hand to push her hair behind her ear. His arm is visible up to his forearm and the shackle is nowhere in sight. However, in the next, wide shot, the shackle is suddenly up around his wrist. (01:01:20)
Chosen answer: They surely clobbered him badly enough that he fell unconscious, and he didn't wake until the guards saw him. Also, they tied him up in the correct position and gave him a good push.