I had the same problem with my P938. My skin was being pinched between the right ambi safety and the grip. I relieved the grip slightly to eliminate the pinching.
Be careful, the right grip holds a small pin in. If you remove too much of the grip to eliminate the pinch, as I did, the pin will come out to the right.
If you remove too much of the grip and the pin comes out, you can stake the pin in place on the right to prevent it from coming out.
I don't like ambi safeties on my carry 1911's and wii try to find a larger lever, one sided safety for my P238.