Maintenance Loan P/T online, but 120 credit a year on 3 year course

I applied for Maintenance loan for an in person course, and I had full maintenance award given. I am unable to do the in person course though so I have applied for online. Although it's the same amount of credits as an in person course a year (120). My maintenance loan has now been approved and it's the lowest. Despite my parents income being under 25k. How can I live on roughly 70 pounds a week? I am really confused because when I applied for the in person course, I was awarded the maximum. How is the the Maintenance worked out for Online courses? and why did SFE want to know what I earned - which was nothing. is there a procedure to appeal the maintenance loan? because there seems to be no breakdown of why I was awarded so little.