Game breaking when you jump

I have recently been working on a stand system for my game, inspired by “jojos bizarre adventure.”

Whenever I make the parts in the stand “massless” the player starts moving EXTREMELY slow. In addition to this, when the player jumps, it will put their legs INTO the ground, preventing them from moving.

Since you need help with your script you have to show it to us.
Copy/paste it here but put 3 backticks (```) before and after is so it formats properly.