A subscription can be cancelled only with the service where you originally purchased it
All your data remains in your account after a subscription cancellation
Cancelling a subscription means to cancel the next renewal
iOS - Apple
Subscriptions bought on iPhone/iPad are managed in your Apple account. For more information on how to cancel an Apple subscription click here.
Android - Google Play
Subscription from Billdu
Log in to the Billdu website with your email address
Navigate to Settings - Subscription
Click on the red STOP button - this cancels the payment recurrence.
Your subscription will continue till the end