I can't find CANCEL SUBSCRIPTION

See -> If you want to cancel a subscription from Apple

If you want to cancel a subscription from Apple - Apple Support

See -> Manage subscriptions on Apple TV

Manage subscriptions on Apple TV – Apple Support (UK)

• You can modify or cancel subscriptions available on Apple TV, including Apple Music, Apple TV channels, Apple Arcade or individual apps.

It is already canceled. That is why there is no cancel button!

Get support from Apple directly -> Get Support or call Apple in your region see -> Contact Apple for support and service or check -> here for more support and assistance.

• You can modify or cancel subscriptions available on Apple TV, including Apple Music, Apple TV channels, Apple Arcade or individual apps.