Product: Credit card or prepaid card

On XX/XX/2019, I was going through the process of buying a mattress on XXXX. As I was about to check out, the company offered to connect my Amazon pay account with purple.com to complete the purchase. I authorized the connection and processed to select a credit card to complete the checkout process. I selected the Amazon.com Store card as it listed : " Your purchase with your Amazon.com Store Card may qualify for one of the following offers ( scroll down for important details and to Print/Save ) : EQUAL MONTHLY PAYMENT AND SPECIAL FINANCING INFORMATION If your purchase is less than {$150.00}, your purchase will not qualify for special financing or equal monthly payments. 

Equal monthly payments - Pay equal monthly payments at 0 % APR : 6 month equal monthly payments on purchases of $ XXXX {$590.00}. 
12 month equal monthly payments on purchases of {$600.00} or more. 
24 month equal monthly payments on select purchases of {$600.00} or more. 
Provided you make your equal monthly payments on time and in full, you do not have to pay interest on this type of offer. If you do not make a payment on time or in full, you will be charged a late fee which will be assessed interest until paid. 
Equal monthly payments required. The required monthly payment is the purchase price ( including tax and shipping ) divided equally by the applicable number of months in the offer period. 

Special financing Pay no interest if paid in full within the promotional period : No interest if paid in full within 6 months on purchases of $ XXXX {$590.00}. 
No interest if paid in full within 12 months on purchases of {$600.00} or more. 
No interest if paid in full within 24 months on select purchases of {$790.00} or more. 
If promotional balance is not paid in full by the end of the applicable promotional period, interest will be imposed from the purchase date at a variable APR of 27.49 %. APR will vary with the market based on the Prime Rate.

Minimum monthly payments are required as stated in your account terms. This required minimum monthly payment may or may not pay off your purchase by the end of the offer period. In order to pay off the purchase in full before the end of the offer period, you may need to make additional or larger payments accordingly. 
To Print/Save disclosure, click here '' Since it stated that " No interest if paid in full within 24 months on select purchases of {$790.00} or more. '' I concluded that my {$1500.00} payment is eligible for 24 monthly payments especially since I was purchasing the mattress during a sale ( which I understood as the promotional period ). 

However, the issuing bank https : //www.synchronycredit.com/ is stating that my purchase is : AMAZON PAYMENTS XXXX WA 12 MONTHS EQUAL PAY 0 % APR AMZ*OnPurple '' - meaning only eligible for 12 monthly payments and not 24. 

I had contacted the bank which told me to speak to Amazon. So I contacted Amazon and they told me that my purchase is not eligible for 24 monthly payments and that the checkout process on Amazon would make that clear. Since I was not buying the product on Amazon and the product was not a selected purchase, I was not given the 24 monthly equal payments. 

The " EQUAL MONTHLY PAYMENT AND SPECIAL FINANCING INFORMATION '' stated during the checkout process does not make that eligibility clear and I believe I was misled as a customer of Amazon and client of both Amazon.com Store Card and  Synchrony bank.