Hi @ Surya kumar,
Does this problematic email have an attachment?
I saw a similar hot issue in Service Health, “ Some users may be unable to see messages with attachments when searching in Exchange Online”: Service health - Microsoft 365 admin center
In addition, I recommend that you use the search-mailbox command to see if you can search for this email in the recipient's mailbox:
Search-Mailbox -Identity "recipient" -SearchQuery 'Subject:test AND from: ******@contoso.onmicrosoft.com' -TargetMailbox "******@contoso.onmicrosoft.com" -TargetFolder "userone" -LogLevel Full
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