Regarding student finance eligibility

My concern is that, I have been in uk since 2013, I gain my residence rights in December 2019 as an extended family member (cousin) to an eu national.After gaining residency card u then become a family member under Eu settlement scheme. My Eu sponsor have settled status and still working. I have also worked continuously for 4 years, got contract, payslip, p60 and pre settled status. I have gained admission to University to undertake bsc mental health 3year course starting 2023/24.
I applied for student finance tuition loan/maintenance which was granted on 27th June 2023, however the maintenance loan was small so I appeal and challenge for more.
I have received an email yesterday that I was initially not eligible for student finance because am not a direct family member so they have cancelled everything and given me appeal right. Is there anything I could do or if u can possibly help?

I hold Ghanaian passport, will get indefinite on 12th December 2024.
But I want to appeal this their decision so I can go to school this year. Anyone who can help me and guide me to appeal it and win, or do I need a lawyer to represent me.