Buy $50 Amazon Gift Card, Get $15 Credit (YMMV)
Amazon has a targeted offer that will get you a $15 promotional credit if you buy $50 or more in Amazon gift cards. The promotion is likely for those who are purchasing gift cards for the first time, based on previous offers. However you can check here to see if it works for you. If not eligible, you should see the following message:
Unfortunately, you are not eligible for this offer.
If you are eligible, purchase clip the coupon to your account and purchase a $50 Amazon gift card. You should get a confirmation after the purchase.