Hi @Albert Ngo ,
Welcome to our forum!
My outlook selectively auto deletes meeting invites and random emails from various people.
Does this issue occur in Web Mail?
And does this issue occur recently? If so, have you done any specific operations before that?
In addition, do other users in your organization encounter the same issue?
As i know, when you enable Auto Accept/Deline option, the issue may occur. Please check the below options are enabled via File>Options>Calendar>Automatic accept or decline>Auto Accept/Deline:
If the options are not enabled, please provide more information about your issue, as i mentioned in the beginning of the reply.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
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