I had the same problem. Refresh/reload the page then click on the cog wheel quickly, click on options, click on mail, scroll down to layout and click on focused inbox and click on don't sort messages. Save the changes. Worked for me 1st time!

Others are saying to click on sent items immediately the page loads first.

This bug is reported, hopefully it will be fixed soon.

More info here - if the above does not work for you

https://support.office.com/en-us/article/Turn-off-Focused-Inbox-f714d94d-9e63-4217-9ccb-6cb2986aa1b2

thanks goodwitch..worked first time...cheers

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