Lug key stripped
 

I thought I stripped a locking lug nut. Discovered when doing DIY rear brake job. Used lug out set to get it off. Other rear tire lock lug came off no problem with lug key. Now I am not so sure it was the lug that was stripped as I was just trying to remove front tires now and the key gets no bite on the locking lug on the first front tire.

Question is, does it sound like key itself is stripped or the lug nuts themselves are? Also, the crappy lug off tool I purchased stripped after using it once so what size 12 point socket do I need to put on locked lug to get it off.