Baskin Robbins

I was a using a promo coupon that was given to me through my phone company. Instead of allowing me to use the coupon, they thought I was trying to get something for free. They would not honor the coupon. I called the manager and was told that she didn't have time to hear about this and she hung up the phone. I have tried to call her manager and she told me she would not give me that person's information. I don't know if I ever want to go this location ever again.