PIP appeal advice needed

I'm trying to appeal re PIP assessment (zero points after Higher Mobility + Middle on PIP - astonishing recovery!) but am having problems re getting appeal advice.
I have found a local legal advice centre but they are very very busy and my advisor, after one visit, says she doesn't have the time to see me again and isn't answering calls or responding to emails.
I'm v scared that this will wreck my appeal chances - has anyone had any luck with finding - free - advice +, if so, how will it look if I change?

Huge thanks - I'm new to this so not sure what should/could ask!