NI contributions not showing although paid tax and NI

Dear Customer Service, I was working full time at an employer from 2016 Sept till 2017 Aug. I just realized recently that my Tax account doesn’t show these months, and none of the NI paid is showing on my Ni record nor the employer exist in my SAR I requested. I am tho unfortunately not found all my payslips from this period and the ones I did does not show my NI number (and haven’t got a P60 from the employer(if I should have). Can you help how to rectify this? NI has been deducted from my gross salary and not sure where it has gone if not to my account. Regards

Hi

Please send as much information as you have to 

HM Revenue and Customs
National Insurance Contributions and Employer Office
BX9 1AN

Please include clear copies of the  payslips that you have, do not send the originals.

Thanks