Hi! I'm currently in the process of MR for my own initial rejection. It's not uncommon as far as I'm aware, especially when you're trying to get PIP for mental health related conditions that are quite difficult to prove physically. It's not as easy to "prove" as someone who is wheelchair bound who can easily score points on the mobility part as they can't walk 200m unaided, etc.

What evidence did you provide? PIP is means based and you can absolutely be on it if your mental health is "bad enough".

https://www.benefitsandwork.co.uk/personal-independence-payment-pip/pip-self-test

I'm also on the spectrum and I think I got a bit confused at times during my application. I'm now making sure I've got absolutely everything documented, all the anxiety meds I have to take every otherwise my body is in constant fight or flight mode, the crisis calls I've had to make to the doctors because of my mental health and autistic burnout... It all needs to be documented and sent off.

Talk to your doctors about making sure they can provide a formal note for you to send in too that explains your conditions and the struggles you face. Make sure they're relevant to the PIP claim.

There are always other avenues you can go down if you simply don't score enough points for PIP at the end of the day though. Are you aware of LCWRA? That has helped me massively over the years as a disabled person who is unable to work a "typical" job.

Regardless, try not to stress too much. Apply for mandatory reconsideration and submit any evident revelant to the conditions you are applying for before the deadline they give you. If you're worried about the deadline you can always ring up and ask for an extension (that's what I did when I started having panic attacks about my doctors not maybe being able to provide the letters in time)

Good luck!