3 identical cards issued to 2 account holders fraud followed

[Ritaed]

Westpac have been invesigating for 6 months unauthorized transactions on our account, 4 of the transactions had the chip card present. Data shows these cards can't be counterfeited so there lies the problem, when these transactions were done both the primary and supp card were in our possession 3 suburbs away, the primary card was used by us 8 minutes later 14 kilometres away. Westpac immediately rang when $3500 was spent at a tobacconist and we told them we had the cards with us and knew nothing of the transactions. We took each card from our wallets and asked Westpac how they knew it was the primary card as both cards had identical numbers.... it is something secret imbedded in the chip that can tell which cardholder card was used. 6 months of hell followed, we handed the cards into the bank next morning and they were destroyed and new cards issued to our home address, requiring only a signature to use. Westpac did not investigate for 2 months as a chip was present, you had your cards, they can't be copied so it had to be you or another member of your family. This line went on for 3 months, even though our kids whereabouts could be verified by CCTV. We could prove that the primary card could not have been present in the legitimate and fraudulent transactions in the time frame, Westpac constantly rang and asked if it could be a family member. Over 40 hours of work we asked the question about previous cards sent to our local branch, could they verify they were destroyed? no, also after we gave our cards back to the bank were further attempts made.. yes. Any rational person could see that if we handed our cards back and another card present transaction was attempted 7 hours later there had to be more cards? A month later the bank confirmed it sent 1 card to an address we had vacated 4 months earlier, 2 cards to the branch where they were never collected, and 2 cards to us which we had, it is now 4 months after the incident. We were refunded the charges after again being asked if it could have been a family member, the next day we were recharged the transactions again, a computer glitch they say. 6 months later we are told that another card was sent to our home 2 years ago, that made 6 active cards and now say they do not know if it was the primary or supplementary cards used as chip transactions do not advise card holder name. We have been put through hell due to the bank issuing 6 cards with the same numbers, 2 we never knew about that were posted to different addresses.Card holders are advised how to keep their cards secure by Westpac, yet this bank issued 6 cards with identical numbers, 1 to the wrong address and took 6 months to find this fact out!! can anyone in the industry tell me if they can distinguish cardholders when chip transactions are done