National Insurance Credits

Hi, I was dismissed from my job after 25 years on ill health grounds in 2016. I was on contribution based ESA for 12 months. I was sent for a WCA and got 0 points. I was too ill to appeal the decision. My ESA payments were stopped. The letter I received informing me of this did say they may still make NI credits. I did not ask for my claim to be closed. When I have asked HMRC if I am still getting NI credits they say I am not. I will have a 2 year shortfall on my state pension.

Can anybody advise if there is anything I can do?