Rig deform problem

Hello, I’ve been using blender for a long time now, but I’ve never run into this before. I made a character and rigged him. I started my animation process, but through the animation, it gets deformed in a strange way. Pay no attention to the floating head, it’s just a low poly version of the head I’m keeping just in case I need it. here are some pictures of it deformed and not deformed:




Any idea why this would happen?

Make sure both the character mesh object and the armature object both share the same point of origin, scale, rotation & location.

Randy