Change the start date and change in Maintenance loan

I am suppose to start my nursing course this September (2023) but due to personal circumstances I have pushed it to January(start date). I managed to speak to student finance and he asked me to inform the university which I did a long time ago, but the start date hasn’t changed in student finance. So do I still need to let d university know or will it get updated automatically before the course start.
And secondly, I applied for the maintenance loan, but the loan approved was very less n I don’t think I can survive with that much as I have a child. I want to reapply for the maintenance loan. So, how do I do that? Do I cancel online whatever they have approved and refill the application form and submit. Or do I need to fill any particular form and send it away to them?
Any advice will be appreciated 🙏🏻