Individuals seeking revenge on bank card fraudsters, as suggested in your article (‘I’ve £80k in the account, here’s my pin’: turning the tables on the scammers, 29 August), might consider enhancing their fictitious card number by using a legitimate issuer identification number, which comprises the initial six to eight digits. It is also advisable to ensure that the final digit adheres to the Luhn algorithm, a checksum used to verify the accuracy of the preceding digits. Additionally, for added enjoyment, one could select a notable postcode, such as SW1A 2AA (10 and 11 Downing Street), SW1A 2JL (New Scotland Yard), or SL4 1NJ (Windsor Castle).

Gary Calder
Chandler’s Ford, Hampshire

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