On 17 Oct, 20:16, GSV 3 minds in a can wrote:
I entered Sudbury hill on the pic line. I realised that there were
severe delays from the announcement. By that time I had already
touched in.
I touched out within 30 seconds of touching in and thought nothing of
it.
The next day £4.20 was taken from my card sudbury hill- sudbury hill.
The guys at the window told me to call the oyster helpline. I was
advised that the credit would be put back on but I have to touch in
within 8 days at a certain station. I nominated kings cross, and was
told that I have to touch in at the piccadilly victoria line entrance
to get my credit back.

The whole system is a farce. On the print out from the ticket office
there is no sudbury hill- sudbury hill journey. It just says pre pay
exit sudbury hill. But at the ticket machine this is clearly visible.
What is going on?

I am not helping answer this question, but I wonder if someone can
explain how "maximum" fare are calculated now, with all the NR and LU
possibilities? (Although I don't know that maximum fares explain
£4.20, which doesn't seem to be enough for two maximum fares, ie
Sudbury Hill to unknown, plus unknown to Sudbury Hill.)

They are apparently "up to" £7. But given that the reason for
charging maximum fares is that the system doesn't know where you went,
on what basis can it ever calculate a different maximum fare from the
maximum maximum fare?