Consumers in Singapore saw a total of $S400,000 ($US235,807) wrongly debited from their bank accounts through a crash in the country's cashless POS (point-of-sale) system over the last week.
Many customers of the Development Bank of Singapore (DBS) were told at retail outlets that their purchase transactions through the nationwide Network for Electronic Transfers (NETS) had failed. Unknown to these customers, the magnetic stripe card-based system continued to debit the transaction amount from their bank accounts.
Some customers were charged three times for repeated failed transactions, while others were told that their transactions had been rejected because they did not have sufficient funds in their bank accounts.
About 4,500 transactions were affected by the problem, which was caused by congestion in DBS's computer clearance system, DBS President Ng Kee Choe said yesterday at a press conference. The NETS system is fitted with a time-out check, whereby any transaction not completed within 45 seconds is rejected.
A surge in NETS use overloaded the ability of DBS's clearance system to respond on time, causing transactions to be rejected, but the bank's internal system had already debited customer accounts, DBS said.
Ng said that later this week DBS will increase the number of communications channels between its own systems and those of NETS from 96 to 128. The bank will also change the current single-lane transaction system to a multi-lane system, and allow a longer time for transactions to be approved. This will reduce NETS errors to their previous level of around one failure per 10,000 transactions, Ng said.
Although DBS said it reimbursed all affected customers within three days, and credited them with an extra S$1 for interest lost, the crash has caused embarrassment to both the bank and customers in a country which prides itself on its advanced technical capabilities.
Apologizing for the failure, Ng said yesterday, "I can understand the frustration and the embarrassment that these customers went through. I myself would be very upset."