Last year TfL automatically blocked a number of Oyster cards topped up during Shop Small.
To minimise the chance of this happening, batch up top-ups and ensure the shop applies the top-up in one go.
Keep receipts! TfL will request proof of purchase to unblock card.
Some Long Shop Name
10 Putney High Street, SW15 4JL
Note: Charges £1 for oyster topup
Crowdsourced data. Not affiliated with American Express.