Contribution based ESA nightmare

I applied for PIP and Contribution based ESA 03/04/2025.

I was awarded maximum PIP allowance, ESA is another matter entirely.....

DWP / Jobcentre contacted me to say I had never paid any NI so wasn't entitled to ESA. Shocked I explained that I had been paying for 43 years and they were wrong. This nudged me to speak to HMRC. I should also explain at this point I've been employed and self employed during my working life more recently over the last 8 years self employed.

HMRC confirmed I had never paid any class 1 or class 2 NI but I had paid class 4 and income tax......
Fortunately I have screenshots of my Government Gateway Tax / NI account from last September when I sent a payment for the odd NI gaps to cover getting my state pension. This is where it gets interesting !

Not only have HMRC stated I have never paid any NI but also deny recieving a payment for the NI gaps last September. So after nearly 3 weeks of data gathering and phone calls to bewildered HMRC staff who confirmed I have a credit in my tax account of tens of thousands but can't access or allocate it my MP and HMRC have launched an investigation to find out what has happened to the 43 years of NI suddenly being removed from my account sometime before Xmas 2024 and being credited to my tax account that no one can now get access to......

I shall keep updating the information as I receive it. I'm wondering if I should speak to a solicitor once this has been investigated and seek compensation from HMRC. What do you think ?

Paul