This is the way I got it easiest was call 650-628-4322 for EA customer services, and select BC2 when it tells you as an option. Then you wait for a operator and tell him/her your having trouble getting the M1 Garand and if he/her asks you for your email for EA just tell him/her and wait a while and after a bit they will ask you to get on BC2 and you should get a popup saying Welcome Back Veteran and you have it unlocked.
this worked i did it