A Scots pensioner fought a two-year battle against the UK government after a scandal led to more than £1 billion of state pensions not being paid.
Jan Tiernan, 81, from Fife, started writing to the Department for Work and Pensions (DWP) after becoming convinced she was being short-changed.
Now a report has concluded repeated human errors made for years were to blame for the massive underpayment of pensions.
The National Audit Office (NAO) said 134,000 pensioners - mostly women - were underpaid because outdated computer systems produced errors.
Jan was one of those affected and was initially told she wasn’t owed any cash. She told the BBC: “I told the DWP I should be getting another £30 a week based on my husband’s contributions.
“But they fobbed me off and said no. I didn’t believe them due to the media coverage, so I started writing to them.”
Jan amassed nearly 100 pages of correspondence with the DWP and received £1280.
But she believes she is still owed more than £17,000 in missed payments.
Jean added: “It makes me sad and angry. I’ve been on this campaign for two years now. It is not just for me but for all of these people who have been done out of this money. They should have got it.
“At 81-years-old, you get fed up with it. It is very wearing and it takes up all your energy.”
Meg Hillier, who chairs the Public Accounts Committee, told the BBC: “This is not the first widespread error we have seen in the DWP in recent years. Correcting these errors comes at great cost to the taxpayer.
“The DWP must provide urgent redress to those affected and take real action to prevent similar errors in future.”
The problem relates to the “old” state pension system where married women who had a poor pension could claim a 60 per cent basic state pension based on their husband’s contributions record.
A review is underway to trace those affected by the failures to award pension rises, dating back to 1985.
Only some women are being fully paid. Others will only be able to claim for 12 months of missed payments.
An estimated 40,000 affected women have already died.
The NAO report found errors occurred because state pension rules were complex, computer systems outdated, and many tasks still needed to be completed manually.
A DWP spokesperson said: “We are fully committed to ensuring the historical errors that have been made by successive governments are corrected, and as this report acknowledges, we are dedicating significant resource to doing so.
“Anyone impacted will be contacted by us to ensure they receive all that they are owed.
“Since we became aware of this issue, we have introduced new quality control processes and improved training to help ensure this does not happen again.”
