Copy rotation works with left hand but not right hand

I’ve created a rig for a character, and the arms are set up as IK. I’m trying to get the hand bone to follow the rotation for the IK hand bone, so I gave it a copy rotation constraint. However, when I try to rotate the IK hand bone to test this out, the right hand bone does not move with the IK bone. The left hand however moves fine with the left hand IK bone.

I’m using local space with parent (hands are parented to a weapon), but I’ve tried local space and world space with no success. The axis of all the bones involved are aligned in the same manner. All rotations and transforms are zeroed. It there anything else that could be preventing this from working?

  1. constraint is active ?
  2. constraint is referencing the correct bone ?
  3. can you share the file ?