Anyone who immediately activated (upon release) the trial version of Apple Music will be automatically deducted from their credit cards as of October 1. If you are part of it and want to cancel this subscription, it must be done now. It's quick, here's how:
From iTunes:
In the top right part of iTunes, there is a user icon. Click on it then enter your Apple ID.
Once done, click again on the user icon menu then click on "Account Information".
At the bottom of the page, search for "Your subscription" then click on "Manage".
Now deactivate your subscription by checking "Deactivate" then in the new small window: deactivate. Finally, click on "Finish".
From iPhone:
Go to settings then press "iTunes Store and app store"
Enter your Apple ID, then tap "Sign In." Press your logged-in username then in the new window, press "View my username".
Scroll further down the page and under "Subscription" press "Manage".
You can now deactivate your subscription for Apple Music, by unchecking "Auto-renewal". Finally, press "Done".
You have deactivated your subscription for Apple Music.