“We are very sorry for any disruption and will ensure that no impacted customer is left out of pocket,” a Barclays spokesperson said on Sunday.

“We are keeping our call centres open for longer this weekend and we will be proactively contacting customers who may be vulnerable.”

The bank said account balances would all be updated by the end of Sunday and that its services were back up and running as normal.

However, reports on the website downdetector, which monitors outages, were still in their hundreds early on Sunday, with most people experiencing problems with mobile and online banking.

Some customers on X also replied to Barclays, external saying they were still facing problems and asking for compensation.

Dave, 69 from Plymouth, told the BBC on Sunday that a problem with automatic money transfers not going through had resulted in him being overdrawn.

“Currently, there’s not enough in my current account to pay a card bill tomorrow, all because of this issue,” he said.

Another customer told the BBC that none of his scheduled payments from the 1 February had been made, and a £500 receipt had not arrived either.

Michaela, 38, from Sheffield criticised the communication updates from Barclays, saying they had been “really poor”.

“I eventually received my late payment but I still can’t use my debit card,” she said.

“Communication from Barclays has been non-existent until yesterday, a pop up in the app saying sorry and not to try and send payments more than once if an error message comes up,” she said.

Barclays is one of the UK’s largest banks, with more than 20 million UK retail customers.

On Saturday, downdetector showed nearly 5,000 issues had been reported with Barclays, more than double the number reported on Friday.

On Saturday afternoon, Barclays’ website said problems with its app and online banking were ongoing, and warned customers that they may face issues making and receiving payments.