A systems glitch this week saw some JP Morgan Chase customers in the New York area have their debit card transactions charged twice.
Affected cardholders had purchases booked as temporary charges but when the transactions were actually processed, the first charges remained, according to Dow Jones.
The problem was caused by a glitch when a bank computer program was changed on Monday but also affected some transactions from the weekend, which were only processed on the Monday.
Chase took to its Twitter 'support' account to seek out grumbling customers and apologise:
The issue was supposed to have been fixed by yesterday and all affected customers will be reimbursed and refunded any fees incurred, says the bank.
The glitch follows an earlier problem experienced by the bank last week, when its online banking site slowed to a crawl and shut out some customers for several hours before the fault was rectified.