When i move any bone of my armature, which is applied to a character, mesh moves accordingly, but then mesh together with bone move a little to the side and sometimes mesh even changes its shape on its own. Why? What do I do to stop this from happening? I have been animating my character for quite some time and I've never seen this happening, it only started recently.
You can try to apply the scale location and rotation . You can do that by clicking Ctrl + a then apply all what I stated above . IF that still doesn’t work then in edit mode select all vertices and click ctrl+n . If all this doesn’t work then I suggest clearing the parents of the rig and the mesh by click alt+p and parenting them again .