On Sep 11, 7:14*pm, "John Salmon" wrote:

"obel15k" wrote

Had the same problem with two cards (myself & partner) which should
have topped-up when we touched in at "King's Cross (Met, Circle, H&C)"
on our day trip to London on 10 Sep. Didn't realise there was a
problem until we tried to exit King's Cross heading for our train home
and one of the cards wouldn't let us through as it was out of credit.

I thought 'out of credit' Oyster cards wouldn't let you *in* to the system,
rather than out.

Indeed - the Oyster PAYG system allows cards to get into negative
credit on exit - however it does kick up a fuss if one has been
charged the £4 'max cash fare' charge, though possibly only if you've
been subject to two such charges (commonly connected with journeys
timing out and out-of-station interchanges and the system failing to
disentangle it all - hopefully recent system changes should make such
occurrences less likely, if perhaps not putting a stop to them
altogether).