two-factor verification method using school Microsoft account

Hello,
I am a student at the University of East London, and I possess a school Microsoft account. My email address is u2081837@uel.ac.uk.
I changed my phone at the beginning of this week and consequently all my data has been deleted. When I try to log in with my UEL account on the microsoft authenticator application on this phone, I am notified that a code will be sent to me on this application to approve my request to log in on this account. I cannot access this notification because my UEL account is not fully logged in.
I cannot access my school Microsoft account and go to the two-step verification area to turn off verification for my old device.
Can you help me? it is very urgent as I can't access Teams or outlook.