Received emails twice for one conversation

[soportebogaris]

On Tuesday the 12th I've received an email at 13:08 and had a conversation sending and receiving some emails on this conversation.
Today, Friday the 15th I openened my Outlook and received as new all these emails again during the night:

If I open the first one I can see the true date time of reception:

If I take a look at the Exchange Admin Center, and look for this email, I can see sent and received events of both days, but I only have one copy of this email:

It didn't happen to other emails or conversations, only to this one. What happened? Thanks for your help.

[#2]

@soportebogaris 

Is this an internal mail flow? M365 to M365?

Another good path to take is to run a Extended Message trace report to check message tracking log (DUPLICATEDELIVER) under eventID.

• https://docs.microsoft.com/en-us/exchange/mail-flow/transport-logs/message-tracking?view=exchserver-...
• https://docs.microsoft.com/en-us/office365/securitycompliance/message-trace-scc#find-related-records...

Polite as usual,

BFN

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[#3 · Accepted solution]

@breakfix_ninja 

Yes and No...I mean, there were multiple recipient mailboxes, some internal from the company and one external non O365. 
It happened only one time with this conversation, so I'll take a look with the Get-MessageTrackingLog you mentioned, thanks a lot.