Thousands of people in the UK have been forced to chase refunds after being charged twice for debit card payments.
The incident occured after card terminals run by Cardnet, a payment service by Lloyds Bank and card processing company First Data, experienced a glitch which led to merchants receiving incorrect settlement amounts.
This meant that money came out of many customers' bank accounts twice, but only showed up once on receipts.
Cardnet state that the issue was only for a short time on Wednesday and that fewer than 5% of transactions were affected.
Customers from all UK banks have been urged to check their account statements to check that they haven't been affected by the glitch.
In a statement, Lloyds Bank reassured customers that their refunds have been processed.
"We anticipate that refunds to cardholders charged twice will be completed by Tuesday 4th September.
"Cardnet sincerely apologises for the issue and the inconvenience caused, we continue to work closely with all parties to resolve this issue swiftly."
Many disgruntled customers took to social media to complain after being double-charged for transactions.
Twitter user Billy Hatch complained that he had been charged twice at German Doner, a kebab shop in Sutton.
"The food cost me £6.49, however when I've checked my bank statement I've been charged the same transaction twice at different time, is there any way i could be refunded?" he wrote.
Sara McCluskey also experienced a duplicate payment after splitting her restaurant bill with a friend.
"@SolitaNQ hi, me and and @orielbird went to the NQ restaurant on Wednesday and have just seen we have both been charged twice for our meal? We split our bill between two cards but have both had the amount taken out twice. Help?"
Some companies recognised a problem with their payment system and wrote to assure customers that the issue was being resolved.
The Nabs Head pub near Preston wrote a statement on Facebook addressing the payment glitch.
"We have been informed of an issue with our credit/debit card payment processor FDMS where by customers may have been charged twice on either the 29th or 30th August, this will show up on your statement as 2 identical payments.
"The second payment has not (and will not) be paid to us and will be refunded directly to your account asap.
"We apologise for any inconvenience caused but this is out of our hands and is an issue with FDMS that they are working to fix. We are unfortunately not the only business affected."
The John Olivers Hairdressing Group posted a statement to their customers to reassure them that their payment had not been taken twice deliberately.
"Clients who paid by credit/debit card for their appointments on 29th August 2018 will see that the payment is showing on their accounts as being taken twice," they wrote.
"To reassure you this is purely an issue with Lloyds Cardnet and that John Olivers has not taken your payments twice."
The Cardnet system handles around 1.2 billion transactions a year for many outlets including restaurants and shops, according to its website.