No results for 'today' in search in Outlook for Microsoft 365

Hello community,

Have the strangest issue here that I'm really hoping somebody will be able to at least offer some ideas about...

For years and years I've had the habit of using search folders in each of the accounts connected to my Outlook desktop client, retrieving messages from all the levels of folder hierarchy based simply on either Received or Sent field value equalling 'today'. To my amazement, I just setup my new work device only to discover that such folders are not working, i.e. don't return any results.

Investigating it further using the Advanced Search dialogue I observed the logic that just doesn't make any sense to me:

• Specifying today's data explicitly works - i.e. using a condition Received -> on = '18/01/2023' returns results as expected;
• The above made me think it might be an issue with date format - however, I found out that using the 'Yesterday' moniker also works (i.e. Received = yesterday)!

So, not items missing from the index (as explicit date works), not date format (as 'yesterday' works), but then what on earth is it? 

I tried rebuilding the index. but to no avail. The exact Outlook version is Microsoft® Outlook® for Microsoft 365 MSO (Version 2212 Build 16.0.15928.20196) 64-bit - but I don't think this is relevant, as on another device with the exact same Outlook build those folders work just fine.

Thanks for your time - any ideas will be very gratefully received!