You get a message that your card was charged for your monthly fee to something you don’t need or want anymore. You meant to cancel the service, but it’s only a few dollars a month, and you always forget until you get the next message you were changed again.
A service that connects to your cards and an app that alerts you when a charge is being made. You have the option to ok it, or cancel this particular transaction or all future ones as well, with a push of one button. You can set a default for when you are not available.