My name is***** am sorry to hear that you have this issue, I look forward to assisting you today with your question and providing the best answer possible.
Please save this page to favorites( ctrl + d) so that you can reconnect in case you get disconnected
Please confirm the Outlook version?
2: Are these missing mails comes under old mails or recently send mails
Didn't find you back..
Please let me know if you are still waiting for answer