Monzo customers have been left unable to use their distinctive coral coloured cards after the challenger bank had a problem on Monday lunchtime.
"At the moment we're experiencing some issues. We're really sorry about this and we're working on sorting them ASAP," the bank told one confused customer on Twitter .
Some customers reported trying to pay for things at shops but discovering their transactions were being declined, others said they were left at cash machines in foreign countries unable to get cash out.
There were also problems with access the app to check balances or, well, at all.
"We're working to fix a problem that is causing some card transactions to fail, or the Monzo app to display incomplete or old information. If affected, you may also be unable to login or receive bank transfers," Monzo's service status page read.
"We're really sorry about the inconvenience and we're working really hard to put things back to normal."
Worse, the bank's customer service online chat and phone lines also broke.
"There's a problem stopping our customer support team from answering chat messages and phone calls right now. We're really sorry about this, and are working to fix it ASAP," the status page went on to say.
"HELP!!!!" one customer wrote. "My joint account has disappeared from the app with all of our money!"
By 2pm, the bank's service status page said the "incident has been resolved", but some people were still reporting issues to it on Twitter.
But by 2:30pm the bank then updated it to say there were problems again.
"We've been experiencing some issues with our platform, but card payments should now work if you wanted to try again," Monzo said.
The bank has more than 2.5 million customers in the UK.
