Due to waiting for and receiving a lung transplant in 1995, he received disability benefits from 1995-1997. Social Security claims we were overpaid $13,000+ and wants us to pay it back. However, in 1997 we paid back $10,000+ in 3 separate checks and were told our balance was zero. We moved in 1999 and weeded through our file cabinet, burning records we thought we would no longer need. On 3 occasions we had been told our balance was zero. Now, 2009, Soc. Sec. is again requesting pay back. We no longer have records and they claim they show no record for the 3 large repayment checks we sent. Our credit union tells us they don't keep records that long! What can we do to recreate what we paid so we don't repay what we've already paid?

If you are in the US these transactions would have been reported to the IRS - the checks you received would be income and the return of benefits would have offset your income for the year they were returned.

Otherwise if all records were destroyed I see no way to prove your claim.