Pip has been renewed for 4 years without assessment

Hi I started claiming pip in 2018 after numerous surgeries on my back/spine/discs it’s always automatically reviewed and re awarded every so many years, I’m going through treatment for these things in the last 6 months as it’s hard to see a neurologist to be re assessed but I’m having further treatment again for it now, I have never been rewarded for mobility only daily living standard which I felt was necessary

I feel like my symptoms have got increasingly worse over the last 12 months, but I’m worried if I make a change in circumstances it’ll be removed completely!

What are your experiences with re assessing as I know I’ll probably have to have a face to face assessment for the first time in about 7 years, I’m just nervous I lose it all because during this time I don’t have a paper trail of treatment just medication here and there for flare ups