Does this work by... first encounter with the card, the system simply accepts it and issues a ticket, but then if the transaction isn't honoured, subsequently refuses it? If so, I'm wondering what the mechanism is to 'Reset' things so the card is accepted?

The background to this: on a rare trip on Bath's 6/7 bus service, the guy in front of me to his surprise found his card rejected so I paid his fare but I then wondered if his debit card was forever blacklisted.

Mark

 
I do not know the full answer to this. However, watching the current "Fare Dodger" programme on Ch 5 implies that on TfL a debit card with no credit will just keep on working the barriers and racking up thousands in unpaid fares. So this seems to mean that public transport systems do not always recognise a cancelled card.

Wiser heads may be able to comment with more certainty?

 
Unless the ticket machine has a signal it cannot validate the debit card.  I suspect that the machines are designed to work locally and the details are updated at the end of the day.  Procedures to pass a black list of bounced debit cards back to all the ticket machines would then prevent future use of the card for n days.

 



[/quote]
I can remember, many moons ago, using a UK debit card in an ATM in Washington DC. The receipt informed me that my balance was now $99,950. I assumed that there was no real time link to the ATM and numbers were just totalled daily/weekly or something. I didn't try the balance any further !!!

 

My understanding of the TfL system is that it works in "transit" mode, an offline mode to speed up boarding and similarly at ticket barriers. Everytime you tap your card is recorded and eventually uploaded to TfL central computer who then calculate how much to charge you. They will try to take the funds in the early hours of the morning. If the card is declined, I think they try again and if still declined they will block your card at every terminal and gateline until you contact them to pay up.

From TfL

 
At my employer, our machines are offline. They’ll take payment when next connected to a company wifi network.

Some bank cards do not allow offline transactions, and the prefix numbers of the card indicate this, they’ll automatically decline.

If a customer has used a card that allows offline, but it’s been declined when collection of funds attempted later, that card number is added to a “hotlist”. A card remains hotlisted for a period of time, and will not work.

If a transaction fails we are instructed to repeat no more than 3 attempts.

We are instructed to allow travel, and ask the customer to attempt to purchase a valid ticket through the company app (online live transactions), if they have no cash.
Majority of passengers we will invite to sit down, and not worry too much. Issue a zero fare ticket, so the company have a record of where this has happened, if there’s a pattern that a zero fare is being issued at the same stop same time every day they’ll consider sending management to investigate.
As drivers we are told not to create conflict, and reminded we are out there alone. It isn’t worth delaying 50-100 other people or get assaulted or worse over a fare of £3. Lost revenue in this situation is estimated to be tiny. (This applies to where I work, and other operators may have different expectations on policies for drivers to adhere to)

Under no circumstances are we to leave a vulnerable person, or someone who could be at risk if we leave them behind. In my opinion anyone can be vulnerable, many disabilities are invisible. So I’ll never leave anyone behind unless they’re endangering safety of the bus.

 
Thanks for these explanations.