Go here: https://apps.apple.com/account/subscriptions > tap on 1SE > Cancel Subscription.

Go into your iPhone's Settings > [your name] > Subscriptions > 1SE > Cancel Subscription.

Go into the app's Settings (tap on your profile picture at the top left corner of the home screen) > gear icon at the right > Manage Subscription > Cancel Subscription.

This is the only way Apple allows subscriptions to be canceled. 

Note: Cancelling a subscription will not refund any payments you have made. It will only stop you from renewing your subscription. Please talk with Apple for a refund of the remaining time on a subscription.

Here’s a helpful Apple article on it: https://support.apple.com/en-us/HT202039#subscriptions

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Tags: #unsubscribe #quit #reimbursement