Sfe- underpayment? Back payment?

So, my parents have refused for my first year to provide evidence of their income because I had my own house for 2 years before deciding to move across the country to go to university. I’m just finishing my second year and they finally agreed to send in their tax report as I’m getting the minimum and cannot survive. They sent it in just before the last payment came through for summer. Will I be reimbursed for the year or term? Or do I have to take the L again? They have said I don’t qualify to be an independent student since I haven’t rented my own house for longer than 3 years. (I was homeless during the summer before the pandemic up until august 2020) so I don’t have proof sadly.
Any help for student finance?
I can’t get a bursary from the university due to student finance putting me on the minimum loan.
My parents made £16k altogether so I should be getting the max loan?