FNB cheating me on my Netflix eBucks

I changed my Netflix debit account to my USD Global Account virtual card last month. The $13.20 was deducted on my account on the 27th of August. However, FNB did not give me the eBucks that I am supposed to get for the Netflix account. The only requirement is that I should be using the virtual card to pay, of which I did. Why is FNB not giving me my full eBucks for Netflix?