Hybrid environment with on-prem Exchange 2016, Outlook 2016. This doesn't appear to be a setup issue as it is only affecting a single on-prem user (UserA).
When any O365 users send an email to UserA, it never reaches UserA's inbox. No issues with UserA emailing to O365 or other on-prem users.
No bounced back notification to O365 senders. Also verified that UserA is able to send/ receive emails from outside of organization.
Verified no Mail Flow restrictions on UserA.
Any help is greatly appreciated. Thanks in Advance.