Where is my $100 Reward Card?

After receiving a phone call from my AT&T agent, I agreed to switch over to AT&T U-verse with a promise of a $100 Reward Card. My service began on May 22, 2015 and I was told to wait 30 days before my Reward Card was to be mailed to me. It's been over 90 days, so I called AT&T inquiring about this Reward Card. The agent on the phone sounded as if she's never heard about this Reward Card program and told me that there was nothing in my account that indiciated anything about receiving the card. I have looked on their website and I do see this Reward Card being offered for new customers. Has anyone received theirs? If so, how can I receive mine?