If you want to cancel an Apple TV+ subscription from Apple, do as any one of these describes (pick one):
- On any of your Apple devices: How to cancel a subscription from Apple - Apple Support
- On an Apple TV box: Manage subscriptions on Apple TV - Apple Support
- On the web: How to cancel Apple TV+ - Apple Support
- On third party devices with the Apple TV app: Manage subscriptions in the Apple TV app - Apple Support
- On a PC with the Apple TV app or iTunes app: Use a Windows PC to cancel subscriptions from Apple - Apple Support
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… but have not watched any of the programmes as each time I tried, all other channels were unaccessible!
I am sorry to hear that.
On what device and model was this happening?
An Apple TV+ subscription gives access to “Apple Originals”; the Apple TV+ catalog of movies and TV shows. Not other channels, not buy or rent content. Those are separate from that, and will have to be paid for separately.
About Apple TV+ - Apple
Apple Originals - Apple TV+ Press
List of Apple TV+ original programming (episodic/series) - Wikipedia
List of Apple TV+ original films - Wikipedia