Disable Focused View
Focused view is a new feature that is enabled by default for new users. It will attempt to automatically filter your emails based on what Office 365 thinks is important to you. Most staff however will prefer an unfiltered view to make sure they do not miss anything important.
To disable Focused View in Outlook
Step 1 - Open Outlook and make sure you are viewing your inbox folder of emails
Step 2 - Click on the View tab at the top
Step 3 - Click on Show Focused Inbox to disable
To disable Focused view on Outlook Online
Step 1 - Navigate to outlook.office.com or open Outlook Online how you would normally.
Step 2 - Click on the settings cog in the top right corner
Step 3 - Toggle Focused Inbox off