My problem was similar, I got on the bus on the 8th October at Clapton Pond and touched my oyster card knowing full well that I had topped it up with £30.00 few days ago. I couldn't remember whether I saw the green light or sound of bleep because at the same time I was asking the driver if the bus was going to Victoria.The front of the bus still said Clapton pond when I got on it. The driver then started changing the sign.The ticket inspector got on the bus a few stops later and he was on the bus for sometime as he was issuing a ticket to another passenger. He came round and told me my card was unvalidated. I couldn't believe it. I said to him that it couldn't be true. He then went to check to see if the machine was working and said that there was no problem and issued me with a penalty. I think that this is unjust. How are we supposed to know whether the card was validated or the money was taken out or not. This was a genuine mistake and people like me should be given the opportunity to pay for the fare. I think this company called the IRCAS are out to make money out of innocent people. I refused to pay the on spot penalty fine as I wanted to appeal against it. I felt that the cameras would show that I have touched the machine. In the end I just paid the £40 or would have ended up paying £80.00. I feel very annoyed and cheated by TFL. I am an honest passenger and feel I have been unjustly penalised.