Maintenance Loan - Changed my mind.

Hi. The issue that I have is that I now want to choose the maximum maintenance loan. When I originally applied I chose to take the standard maintenance loan but I was eligible for the maximum maintenance loan which was about £7,400. I've received the letter of my application being approved and it shows my loan amount is £3,410. My parents want me to change that amount to maximum maintenance loan amount as it will be beneficial for us. So I try attempt to change it by logging in to my account and changing my application. I am given two options when I try to change my loan amount online. 1) to take max amount which is £3,410 or 2) type in a specific amount I want. I am confused because I was eligible for the maximum loan amount of about £7,400 but it says my maximum loan amount is £3,410. Shall I get my parents to support my application? Is there any way to change my maximum loan amount? please help.