Microsoft 365 Problem

I have a current active subscription for Microsoft 365 which is paid for through my apple account. Every time I try to log in to Word, I get a notification that I need to sign in. Prior to the IOS 18 update, I was able to sign in (which I felt was unnecessary to have to do each time on the same device) using the email and password created. Now, it no longer works. I can view my older created documents but cannot create a new one from a blank page. I feel like I should be reimbursed for payment for a subscription that is now worthless if it can’t be resolved.

Anyone else having this issue? If so, can you please help me?

—Thank you