Any time you have trouble with a Microsoft 365 product (Outlook, Word, Excel, OneDrive, etc) use a web browser to go to cloud "ground zero"
at http://microsoft365.yourcompany.com*
Everything else, like the Outlook program installed on your computer or on your phone, is secondary.
So if there's a problem, try going directly to Microsoft 365 in a web browser first.
Once you know your account is working properly in the cloud in a web browser, then you can tackle troubleshooting the software or apps you might be having trouble with.
* Note: The address
http://microsoft365.yourcompany.com
or
http://m365.yourcompany.com
should take you directly into your Microsoft 365 Business account on the web.
If it doesn't, your company's domain may not be set up completely. Contact your system administrator or you can contact us for help.