[Resolved]  British Airways — Ticket Refund

I had booked two tickets for a return flight to Europe on 28th March 2013 and paid Rs 1,39,984.
The booking reference was 8U3SMZ.
Due to a change of plans I applied for a cancellation on 4th April 2013.
On 10th April I got a refund of Rs 63,842 into my credit card account. On checking with them I was told that this is the amount of refund for ONE ticket, after deducting the cancellation amount. I have been asking them that why only one ticket, they insisted that they have processed both the tickets.
I have been in constant touch with British Air for the past one month and I keep getting the same answer that we are in touch with our London office and they have not responded.
I have even asked them to give me a transaction reference for the second refund so that I can ask my credit card company to try and track it, but even that is not being given.
This situation has led to financial difficulty as I have had to pay the amount to my credit card company, who have billed me an excess of Rs 76,142.