Citibank Prepaid Card Complaint

Citibank Prepaid card department,

General purpose card Managing, opening, or closing account California

I got 2 Pre Paid Debit Cards issued as a Reward by my Employer one for $500.00 & Other for $250.00. The Cards Had an Expiry Date of -. I did not use the cards before the expiry date and all the Funds ( $750.00 - in total - were unused and the cards expired. When i contacted the Issuer ( Citi Bank - to ask about re-issuing the cards for the remaining amount - after deducting the applicable Monthly Maintenance Fees ( $3.00 Per Month as outlined in the Service Agreement ) - i am being told that, the Balance Amount Can not be returned. The Card Holder Agreement Does not have a forfeiture class where in it is indicated that the unused funds will be forfeited after the expiration date. I am shocked upon knowing that i stand to loose $750.00 - even when i am ready to pay the monthly maintenance fees. Can you let me know - what options are available for me to pursue recovering the unused funds - $750.00 - and how to get this done? Sorry..I was out - and hence ca n't attend the call. I talked with my employer and to the Citibank too. But they again confirmed that I wo n't be getting my money back. Thanks.