Credit Card Programs - Credit Card Bonus Signup Disputes

I've noticed on FT a few mentions that FTers have signed up for a new credit card with a specific signup bonus, usually at first use and after a spending amount, only to have the CC company not pay up. I've just had that experience with Amex. When I called to politely ask about what happened, they responded that their records did not reflect that I was due a bonus. I said I had a screen shot of my application with the bonus clearly spelled out. They muttered that they would investigate and get back to me in a few months. Hardly what you expect from Platinum service. The same thing happened with the JPMorgan British Airways visa card recently. At least they accepted that they owed me 50,000 Avios, even though they admitted they had not sent it as required. In both cases I noted that the email from the banks accepting me for the cards, makes no mention at all of the mileage signup bonus. Is this an organized way of squirming out of their responsibilities?

http://www.flyertalk.com/forum/american-express-membership-rewards/1325762-bonus-disputes-amex-avoiding-them.html

I feel the same way. I called chase for my 65k + 50$ credit and they said yes at first but now they r saying yhey will send it in for review. I think gone r the days if big bonuses.

chase has been pretty good with bonuses with me so far... only AMEX has been a pita.