But from the OP's account, it seems that the old card was used before the new card. And the question is why was the card initially accepted at the TFL gateline (as opposed to card declined) and then later declined?
But that’s the thing, I haven’t used the new card for anything yet. I went out, using the old one, and found the new one had arrived when I got home. I didn’t go out anymore, all I did was add the new card to my account but left the old one in place, with the intention of removing it once payment for yesterday had cleared.
Contactless payment is taken by TfL overnight which is why it appears as a single transaction each day. I suspect that applying a new card to an account will lead to TfL seeking an authorisation against that card immediately (to confirm it is valid) which a bank would see as the card being used.
That's an anti-fraud measure which has always been in place with contactless. With the contactless limit increasing to £100 it means fewer routine chip and pin transactions are being made (which previously would've confirmed the pin without you even realising). The consequence of this is that customers are having to confirm their pin more often.
I believe that is the correct answer and the issue is effectively TfL's systems. An unusual timing of actions has had the result described. Just need to pay again.
It is not at set intervals like 3 or 4. Clearly if we all knew how often and why so would criminals. It's a combination of numbers of transactions, amounts, nature of transactions and where. You could possibly go a dozen transactions without needing a PIN.
Looks like the forum hive mind has got the answer.
Happened to me with my bank.
Yes that's correct, though app payments like Google, Android and Apple pay simply work anyway as they are more secure
