Cannot update macOS Mojave 10.14.2 to 10.4.4

I have a Mid 2012 MacBook Pro with 512 GB hard drive which dual boots along with macOS Sierra.

I have converted macOS Mojave partition to APFS from Mac OS Extended (Journaled).

When attempting to install macOS Mojave 10.14.4 update, this screen stays for a while and then system restarts to back to macOS Sierra:

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What is going wrong and how do I resolve the issue?