Yesterday, by mistake and in haste, I tapped my credit card details instead of my train ticket, in my Apple Wallet, on returning to London from Sheffield, at the barrier at Kings Cross.

TFL have charged me 10p. I am expecting to be charged for the fare, but will dispute it, as I have already paid for my fare and have the ticket to prove it.

I am now getting messages saying Payment Has Been Declined.

Does anybody know how to interpret this please?