Changing Mesh Not Saving

Hello guys! So I have been trying to solve this issue for over 3 weeks now.
The issue is, I have a player and it works fine, but if I go into the mesh, and rotate a bone or something. It just resets and does not save. I have been clicking the save button and all so it should save just fine. I just cant figure it out. I will attach a video below of the main issue!

If anyone can help that would be great! Thank you everyone!

[VIDEO]