I'm curious about something,
Bungle73. You were very quick to condemn the employee you interacted with as 'telling a pack of lies', in effect assuming the worst. You seemed unable to have the common decency to give her the benefit of the doubt and consider she made an honest mistake, and decided she was for some reason trying to make a criminal out of you and wrote a letter of complaint against her, fuck knows in which terms.
That is a deeply regrettable thought process to have IMO, but aside from that I also noticed from your account of the events that the ticket barrier itself had first thought your ticket was invalid, or at least there was something to be queried about it. As well as writing irate letters to LU complaining about this woman and probably getting her in a spot of trouble for what it was clearly a mistake, did you also fired off angry letters to London Underground Ltd and or TFL also accusing their computer networks of lying and trying to paint you as a criminal? Or are your rants and zero tolerance towards mistakes reserved for human beings only?