Amazon Bait and Switch Internet

I was making a purchase on Amazon and bit on the "$50 Off This Purchase When You Sign Up for an Amazon Credit Card" offer. I went through the application process and was approved, but the $50 off was not honored. I called and was told the credit would be applied to a future purchase. So I told the rep to retract the credit application but she said that had been forwarded to Chase Card Services. Called Chase and they said they couldn't cancel it either.

So I ended up paying full price and with a credit card I didn't really want. BAIT AND SWITCH.