Hi @K Vijetha ,
Do users accepts or declines the request in Outlook desktop client or some other where?
If yes, from the perspective of the Outlook client, as I know, Outlook provides an Accept but do not send a response option like below to avoid troubles like yours. If possible, you could tell users to respond with this options.
By the way, you could also use Outlook rules with specific words(such as "Accepted:" or "Declined:") in the subject to manage those meeting-response emails.
Hope this can be helpful.
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