Puzzled at Nat Ins record gap & unsure what to do

[salsamad]

Got my State Pension forecast and my National Insurance Record yesterday.
Noticed on my record that in 1984/85 it’s showing as no contributions were paid. I started work in my first job after finishing college in Sept 83 as a full time Nanny. This employer paid contributions for tax year 83/84 but then obviously not for following tax year 84/85 - I left for another job in July 85.
I have no proof of this employment or my pay from this time - I have no P45 or P60 and was paid in cash without any payslips.
I can chase it up with HMRC by writing a detailed letter (I rang them today) but without proof I’m wondering if it’s worth it? I was also wondering if they could then request back, payment of tax from myself for that year, if this wasn’t paid either? I don’t even remember what my weekly pay was.
Will I be making life difficult for myself chasing this missing year of contributions? (I don’t have full pension due to recent missing years so am looking to pay voluntary contributions going forward).

@salsamad as you were never given payslips or P60 it is likely that your employer did not pay you via PAYE and instead opted for cash in hand.
As this was 40 years ago it is going to be impossible to resolve this without payslips, P60 etc.
As it is just that one year does it affect your pension forecast?

Sorry realised it does make a difference - honestly it will be far easier to pay voluntary contributions.

You won't get any credit for the year without any evidence. You'll be wasting time all round. Best to pay the voluntary.

Thanks for the replies.
I think what’s confusing me is they definitely did pay contributions for the first year of my employment with them. I can’t understand why the following years non payment wasn’t followed up around that time by HMRC - I must have had a P45 off the employers before I left for my next job but honestly can’t remember now .

@salsamad This was nearly 40 years ago, IT systems were nowhere near as sophisticated and there were a lot of manual processes.

If I read your op correctly:
1983/84 - you have a record
1984/85 - no record
1985/86 - left July 1995 and you have a record.
Your P45 would only have shown earnings from 6 April 1995 and you have a record for that year.
In the 1980s there was high unemployment so a gap may not have been unusual.