TfL. Train Oyster checking

Just recieved my mondo card, think it’s great. But I’ve been using it as my Oyster card on tfl overground and have been checked twice in the last 3 days by conductors who check you have tapped the oyster reader. Of course I always do, but the card has always failed the card reader test.

I then have to explain its a new card connected to an app and each time they look at me puzzled and walk away.

I am worried though that i will be fined one day because the card fails the oyster reader checker.

Is this something others have experienced, are there plans to make the mondo/oyster sync more immediate?

Not experienced myself, but it is a known issue:

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Yeah this is a known issue. I’ve had mine checked numerous times on the DLR and no one has said anything.

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Again, this is a long standing known issue.

I could talk for a long time on why it only affects the ticket inspector handhelds, how TfL contactless works at a high level and the technical choices TfL made to get here with this issue. The short answer is that the handheld readers will try to authorise an offline transaction for the amount of the maximum fare and then either drop it or commit it to the payment networks later when the journey history for the card is all collected and calculated.

Monzo cards are, at best, weird about offline and will almost always reject any attempts at an offline contactless transaction, forcing the terminals to go online for the instant notifications and card freezing feature to work. This rejection causes the handheld readers to error out and fail your inspection.

The good ticket inspectors will just ask if it’s something like a foreign card and let you go, others want a bit more explanation (you should use the line from the known issues post, trying to explain the technical side gets you in even more trouble :blush:).

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