American Airlines not refunding a cancelled ticket

I bought an American Airline ticket from AA.com and paid for it using Paypal account.

I had to cancel the ticket a month before departure and asked for refund. I was told that the refund would be issues in 3-5 business days.

After 2 months I contacted the refund department and they told me that they have already processed the refund and it has been sent back to a credit card ending in 3742.

I have an open ticket with the refund department but they keep sending me email that they have sent the refund back to the credit card from where the original payment came. I DID NOT use any credit card to pay AA.com for the ticket so why are they sending the payment to a credit card? Even if they made a mistake and sent the refund to wrong account, why won't they check the original transaction send the money back to my paypal account?

Here are the details of the ticket opened with refund department:

Ticket No: 0012301602649

CONTACT INFO:

AddressLine1: 542 Mill River Ln

AddressLine2:

City: San Jose

State: CA

Zip: 95134

Country: USA

Email: btripathi AT gmail.com

HomePhone: 408-463-6397