Hello @lloyddavis. I can totally relate to your situation. Even I have faced difficulties while traveling in the world famous tubes. Sometimes the card doesn't get out of the automatic access doors and you. Loose the ticket. Now all you can do is to buy a new one and think that a limbo machine has just gulped your hard earned money.
And this on peak, off peak pricing is a complete facade. You got have a digree in aeronautical sciences, just to decode all permutation and combinations... 😛😜
Peace ✌️