This article provides a workaround when encountered the above issue.
The original Native Key provider which generate the host deleted by user and they create a Native Key Provider with the same name, but the KDK and KeyID are not same with the original. So the host key can't be resolved after host upgrading/rebooting
The user has to restore the original Native Key Provider by backup file and should not re-use key provider names unless the key providers really are the same logical key provider.
Rekey host key by invoke api hostSystem.configureCryptoKey from mob with new default key provider if they can't recover the original native key provider.