Texture paint mirrored (friend needs help!)

Hello! My friend unfortunately doesn't have reddit so he asked me to ask reddit for him. He's ok blender trying to paint over a object texture.

This is what he said:

"Does anyone know how I can fix this texture because when I draw on it, it mirrors it into the other side of the mesh and I don't want it to do that I want to be able to texture draw on one side of it without it mirroring"