Rockstar Activation Code Already in Use (Steam) (Verify) (90% don't work)

This may work to the Social Club version alone as well. I mean its the same process, just in different ways of Verifying the game file. If you are getting this "Rockstar Activation Code Already in Use" message AFTER you have already activated the code once before, no worries at the moment, you can try checking the box that labeled "Remember Me" in the Social Club Menu/Loading/Login page, and try logging in that way. At least it worked for me, so Good luck!