Cloud storage Q
How do I turn off the 5GB of cloud storage since my company is no longer paying for the additional service?
Question marked as
The default 5GB of iCloud storage is provided completely free of charge with your Apple ID. As such, there's no way to 'cancel' it (nor would you want to, I think).
If you had a larger iCloud+ plan, and want to downgrade to the free 5GB iCloud plan, see here - Downgrade or cancel your iCloud+ plan - Apple Support