Hi @Rachel Jackson ,
Welcome to our forum!
Does this issue occur with all emails or the specific email?
And does this issue occur in Outlook desktop client or Outlook Web mail?
If the issue occurs in Outlook desktop client, in order to check if the email is still in your mailbox, please first check the Deleted Items folder. And then it's suggested you could try to search in your Outlook and remember to change the search scope to the current mailbox.
If you find the email is in another folder, please check if you have created some rules to move it.
If you still cannot find the email, please check if it is permanently deleted.
Hope the above help!
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