Had a look on the Gov pension website and although I have paid my NI every week for 3 years over the last 11 none has been paid in by my employers. I don’t no how to put a link but it may be worth having a look.
It may be worth you e mailing this information to HMRC pretty sharpish mate.
I think it’s to late for the first two years as it was 10 and 11 years ago and the firms no longer there, but they had about 20 workers so if they have kept all the money it’s a hell of a lot. As far as HMRC they should no because they put it on the pension website going back to early 70s.
Report it…i worked for an employer like that…then i had a heart attack, and he denied i ever worked for him. and i couldnt claim one penny from the government…i soon sorted that out by contacting every company i had delivered to, where i had to go on the weighbridge, they kept records…and proved my case…he eventually was summonsed and had to pay all the money back, plus a very large fine.