"The suit says Amazon gave the Hermans little notice to cancel the order or to shop around because it notified them of the latest price increase in an email at 8:54 p.m. — the same night it processed their order and charged them."
That's the thing that's caught me out on this a few times, too. You don't get much time in between being reminded of a subscription and notified of the amount before the payment is taken. Very easy to miss!