Please help with never received prepaid gift cards!

We bought 4 phones on December 27th, and we were told by the Xfinity sales person that each phone qualified for a $200 visa gift card. After waiting 3 months, I went to my local Xfinity store where I was given a number to call the Xfinity Incentive Tracker. The person I spoke with on March 22nd had nothing on file for me, but gave me a reference account number, and told me she was going to give my information to the escalation team, and that I was to call back by April 14th if I hadn't heard back from them. So after not hearing from them, I called back on the 14th, and the woman (Carrie) said they were still looking into it, and that it had to be 90 days from the activation for them to start processing it. I told her that it had already been over 90 days, and the only thing she told me was to call back next week to see if they had started to process the gift cards. Needless to say that I'm angry, frustrated, and very disappointed! Customers shouldn't have to go through all this hassle for something that was promised to them! It makes them (The Incentive Team) and Xfinity look dishonest, and now I'm regretting switching phone carriers. To those that have received their gift cards, could you please give me some advice of how to handle this? Or is there an Xfinity employee that could help me resolve this issue?