Lionsgate subscription from iPhone not appearing on Apple TV

… not appearing in apple tv

1. Is this about the Apple TV app on a third party device, or about the Apple TV box? Please specify.
2. Did you subscribe in the Lionsgate Play app on iPhone, or did you subscribe to the Lionsgate Apple TV channel (as available in select markets)? Your subscription overview would list if it is for the Apple TV channel.

If you are signed in to the Apple TV app on Windows with the matching Apple Account, then it should have the same channel access. When that somehow doesn’t happen, then please contact the Apple Support staff for further assistance. Contact Apple for support and service (phone numbers) or start your support request online (chat/​email/​callback).

Apple TV channels should be fully supported on Windows, per:

Subscribe to Apple TV channels in the Apple TV app on Windows - Apple Support