Hi Susan Hooper,
One thing that may help narrow this down is determining whether the missing emails were actually delivered to the account during the two-week period after the compromise.
If you have already regained access to your Outlook account, try reviewing your account activity and mail settings for any unexpected changes. In some account compromise cases, forwarding rules or filters may have been added, causing messages to be redirected to another folder or even another email address without the account owner's knowledge.
You may also want to contact a few of the people who sent you important emails during that period and ask whether their messages were successfully delivered or if they received any non-delivery reports. This can help determine whether the emails reached the mailbox in the first place.
Please note that this is a user-to-user support forum. Moderators, contributors, and other community members do not have access to Microsoft's back-end systems and cannot determine whether specific messages were delivered, moved, or deleted from an individual mailbox.
Have you already regained full access to the account, and are you currently able to send and receive new emails normally? That information may help the community suggest the most relevant next steps. Thank you so much for your understanding.
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