Hi prada experts, I got a question for you. When you purchase a prada bag at the dept. store - Barneys, NM, or Saks, do the dept. store stamp and mark the date of purchase on the prada authenticity card? I am asking because I bought a prada bag at Barneys and the SA didn't stamp the authenticity card, and I am not sure if the warranty is still in effect should I need to send my bag to prada for repair.