Tested on: Outlook shared calendar permissions, Teams mobile calendar view, account refresh behavior, and Microsoft 365 calendar sync checks.
Teams mobile shows calendar data from the signed-in Microsoft 365 account, but it does not always surface every shared Outlook calendar immediately. Permission type, account mismatch, mobile cache, and recent sharing changes can all make a shared calendar look missing. Start by proving the calendar is shared correctly in Outlook, then check the Teams mobile account and refresh path. That separates permission problem