I have my dog rig generated by rigify. Did the additional weight painting and forgot to turn on symmetry. Now I have left side properly weight painted, and right one isn't. Tried to symmetrize painting by removing one side and then symmetry in edit mode, didn't work. Tried with vertex groups by copying proper one, then Mirror Vertex Group, but it always shows some vertices are mirrored, other failed. Topology is symmetrical and bones are symmetrical too. What is best solution? On first two pictures you see left side which is properly painted, and right one which is not. Also, on third there are middle bones (spine) however, it isn't symmetrical to sides.