The problem with this trick as well as someone said about spin the gerbil, is the motion of flipping the yoyo when there are this many strings in the gap as well as wrapped around your fingers. There is a lot of friction in the gap of the yoyo when one part of the string is rubbing against another, and it causes a little play which turns into a bind, or rubs against the response etc… This is magnified when your hands are not lined up with the plane of the yoyo, which someone else already stated. Try to make sure your hands are fairly dry, and use a new string if that helps.
as another note, doing it fast sometimes will also cause the string to bind up, so try doing it slow when you’re learning. You can also look into the gap of the yoyo while doing the trick and see if it is starting to bind, or if the problem lies somewhere else completely. I used to get this problem frequently and it annoyed me too, good luck!