The RediATM network has suffered an outage across Australia, infuriating shoppers preparing for Christmas just two weeks away.
Customers reported that money had been deducted from their accounts, despite an error message appearing on the ATM screens declaring the transaction had failed.
The network claims to be one of Australia's largest, with more than 3000 machines.
Christopher Griffiths, 56, tried to withdraw $100 from a Crows Nest RediATM on Saturday morning. When the transaction failed, he proceeded to use Westpac and St George ATMs nearby, which also did not work.
He checked his online Credit Union account soon after to find a total of $200 from two separate transactions had been deducted.
''If there is a network problem they have to shut it down if money is being taken away,'' Mr Griffiths, from Chatswood, said. ''I was going to buy grocery and petrol but now I'm stranded at home waiting for my dad to bring some extra cash.''
Cuscal, owners of the RediATM network, told Fairfax Media the problem occurred at 10.40am and was resolved by 1.20pm.
''We immediately took action to reimburse cardholders who may have been impacted by an illegitimate debit when they visited a RediATM, and those reversals are currently underway,'' said Loyce Cox-Paton from Cuscal.
''Cuscal sincerely apologises for this outage which has understandably has caused frustration for cardholders, especially at this busy time,'' she said.
NAB is aware of the outage and advised RediATM customers to use NAB machines.
Customer service is instructing people to submit a complaint form on Monday if any problems were not resolved.