How to link Office365 work/student email to Windows 10 Mail app

Question

I find using Windows 10 Mail app really helpful because I am easily notified with the incoming e-mails to my four e-mail accounts.

I have a problem though. My Office365 student account (myMapua) isn't linked properly to the app. The inbox (as seen in the picture) isn't the same one with the one I see when I go to the Outlook Web App. I have a lot more e-mails than that. And my inbox doesn't actually contain that e-mail.

I tried changing the server settings of my Office365 mail in Windows 10 Mail app to outlook.office365.com or smtp.office365.com [source] but it still didn't work.

How do I sync my Office365 student account properly to the app?