JPMorgan Chase Credit Card Complaint

JPMorgan Chase Credit card department,

Advertising and marketing Michigan

On - -, 2015 I was booking tickets on - - web site when I was presented a pop-up, that offered a $50.00 statement credit if I opened a Case - credit card and charged the - ticket to the new card. After several calls to both - and Chase, which resulted in agreement that I should get the credit, followed by letters that state I did not follow some undefined procedure, they claim I am not entitled to the credit. I am still waiting for an explaination of what I did wrong, because the folks on the phone ca n't telll me.