Follow the below steps to cancel a subscription on your iPhone, iPad or iPod touch :
Step 1 : Open the Settings app
Step 2 : Tap your name
Step 3 : Tap Subscriptions
Step 4 : Tap the subscription you want to manage.
Step 5 : Tap Cancel Subscription. Or, if you want to cancel Apple One but keep some subscriptions, tap Choose Individual Services. If you can’t see Cancel, the subscription has already been cancelled and won't be renewed.
Step 6 : Tap Confirm