I wonder if it's a ghost. I tie the ring around my neck like this. When I got up, I found that the ring had dropped, but the rope was not broken. Still hanging around my neck.

This is not a ghost, this knot is actually a ring! You might as well try again. After you wear it around your neck like this, loosen the rope slightly and pull two ropes to both sides until the ropes meet on the other side of the ring, and then the ring is untied. This method of tying the ring is easy to make the ring fall off, so it is recommended to replace it.

I met a similar thing this morning. I thought my wife helped me fall asleep and secretly took it off. About my wife's mistake.