Shared calendars not showing up in Android

This is not a techie blog, but here's my solution to an annoying thing:

Sometimes, google calendar in android does not show up calendars which have been shared to you.

Here's how I fixed it on my Moto G4:

Settings>Apps>Calendar>Data Usage>App Settings>
Now click on the name of the calendar which isn't showing up
Activate 'Sync'

Hey Presto! Sorted.