Matt Patterson, a National Review Institute Washington Fellow, made a critical error with his SmarTrip card. And while I quietly laugh at his pain I'll try to help you out. (I'm sorry Mr. Patterson! I have absolutely no self-control!) Or at least share his story for your benefit.
You see, something happened to Patterson's card and after slogging through his work day he swiped his card to find it did not work. He asked a Metro employee for help, and she allowed him to pass through the swing gate, and when a fellow traveler was engaged in the event, she asked if it was registered before moving on. She appears lackadaisical at best, and unsympathetic at worst. And I am totally on her team, because, come on, isn't this lesson in the paper every few months? Who among us has not learned this lesson first hand?
Now seems like a good time to learn if you haven't: SmarTrip carts are fickle. They demagnetize when you have a high balance, at the hands of credit cards, security gates, and various metal-based activities. So how do we save ourselves from this pain?