Alison Martin, from Charlwood who retired from the civil service, added that she had yet to receive regular payments despite retiring at the end of November 2025.
She said: “I’m more than a bit bitter. I would like to see some rapid movement.”
Capita bosses apologised to the Public Accounts Committee in February over the payment issues.
An emergency interest-free loan system was set up in January to try and tide pensioners over until issues are resolved, which has so far paid more than £7.2m according to the Cabinet Office.
Chris Coghlan, MP for Dorking and Horley, said constituents were “worried about how to pay their bills and mortgages” and that the situation was “very serious and deeply frustrating”.
In an update on Monday, a Cabinet Office spokesperson said about 23,000 pension quotations were currently outstanding.
Capita has committed to restore service by the end of June, they added.
A spokesperson from Capita said: “We have been working together with the Cabinet Office over several months to reduce the backlog and are taking all necessary steps to address this.
“Additional staff have been trained and deployed, and our focus is on ensuring members of the Civil Service Pension Scheme receive the service they expect and deserve, in line with the plan agreed with the Cabinet Office.”
They add: “We are sorry for the worry, distress and frustration any delays are causing.”