Married Womans Reduced Rate

Good Morning, Looking for some advice please. I have requested a copy of the form I completed from HMRC to stop paying the married womans reduced rate NI I have asked for this by letter, in a telephone call, online and a further letter. I have just received a reply to my last letter that says my records show that I commenced the married womans reduced rate on 6th April 1977 and ceased paying at this rate on 5th April 1983. I thought the reduced rate ended on the 5th April 1977 and could not be claimed after this date? If they have this on my record why are they unable to provide me with a copy of the form they sent me that I completed and returned to them to stop paying this stamp. I am certain this was before 1977.

Hi Sandra,
The Social Security Pensions Act 1975 and associated regulations abolished the right of a married woman to elect to pay reduced rate Class 1 NICs and not to pay Class 2 NICs where she married on or after 6 April 1977.  
However, women who had married before 5 April 1977 had a final chance to make an application for reduced liability by the deadline of 11 May 1977.
A woman who had married before 6 April 1977 could keep her right to pay reduced rate contributions if she made the choice before 11 May 1977.
The CF9 forms (the form to apply to pay at the married woman’s reduced rate) are no longer available.
The problem of storing very large numbers of forms limited their retention to a period of 6 years.
owever, it was the Department’s practice to note the person’s permanent NI record if such an election was made.
This is the record that would have been checked before the response to your enquiry was issued.
Thank you.