Why do characters jitter violently on other clients when landing after changing pitch/roll rotation in air?

How do I stop characters from looking like they glitch out (jitter violently) to other clients once they land after their pitch or roll rotation was changed in air? (aka when they land on their side instead of their feet)

Also, how do I post a video of it on here? Every video file format I try says: This attachment is not permitted because the file type is invalid.