Q: I want to deactivate my monthly music subscribe

Learn how to view your subscriptions that renew automatically, change your subscription period, and turn off Automatic Renewal.  View, change, or cancel your subscriptions - Apple Support

If you mean Apple Music just turn off automatic subscription renewal.

You may find the instruction how to cancel it here: Manage your Apple Music membership - AppleSupport

http://9to5mac.com/2015/06/30/how-to-cancel-apple-music-subscription-auto-renewa l/