Using New Outlook on Windows for personal email, calendar, and contact management
Could you confirm whether you’re using new Outlook or classic Outlook, and whether any error message appears before it closes?
If you’re using new Outlook and Repair did not help, please try reinstalling it:
Open Start, search for Outlook, right-click the new Outlook app, and select Uninstall.
Open Microsoft Store, search for Outlook for Windows, and reinstall it.
Open Outlook and add your account if prompted.
Meanwhile, please check whether you can access your email through your provider’s website. Let me know whether Outlook still closes after reinstalling.