CGT Overpayments

I had three share sale transactions between 2004 and 2006 which I returned, as required and within the specified time, to Revenue. In March this year I found an error in a spreadsheet that served these transactions which caused an over-payment on each. The total over-payment was €1,059. I detailed the error to Revenue and, eventually, received a response stating that I was not entitled to either a refund or a credit under Section 865(4) TCA 1997.
Is there no onus on Revenue to check these submissions or can they just ignore the error because of the elapsed time? Thank you.

Capital Gains Tax is self assessed and Revenue would have relied on the figures you submitted. Unfortunately the overpayment cannot be refunded to as it is now statute barred under section 865. If you had discovered the error within the four year time limit for repayment it would have been refunded to you

Many thanks, Clarkey.