Thanks for posting to the Community, @mdixonuk-hotmail.
Let me help cancel your subscription by following these steps:
If you purchased QBO from the Apple App Store or Google Play, here's how to cancel the subscription:
Apple App Store (iOS, iPhone, iPad)
Google Playstore (Android phones and tablets)
However, if you have purchase QuickBooks Online directly from Intuit, you can follow these steps to cancel it:
You can contact our Customer Care Team to process the refund for the unused services subscription. They can also review your account from there.
This article will give you more information about the cancellation process: Cancel your QuickBooks Online subscription.
In case you change your mind, you can reactivate your QBO account anytime.
Let me know how it goes to assist you further. I'll be around to help. Have a great day ahead!