You have migrated a user mailbox with Hybrid remote move to Microsoft Office 365 from Exchange Server 2019 or Exchange Server 2016. When you try to convert this migrated remote mailbox to a shared remote mailbox, you receive the following error message:
WARNING: An unexpected error has occurred and a Watson dump is being generated: remoteMailbox.RemoteRecipientType must include ProvisionMailbox.
To fix this issue, install one of the following updates:
Learn about the terminology that Microsoft uses to describe software updates.