Revolut has been by an outage which it says is impacting "multiple services", as thousands of customers report problems.
Users of the British bank have flagged being unable to make some payments or access funds via its app on Tuesday morning.
Platform outage monitor Downdetector had seen more than 1,500 user reports of issues with Revolut services shortly after 08:00 BST.
"We are currently experiencing a service disruption affecting multiple services," a Revolut spokesperson told the BBC - adding "we can confirm that all our customers' money and data are safe."
"We've been working to fix the issue since it was identified this morning and apologise to anyone affected and for any inconvenience caused," they added.
A page on the company's website showed a range of services were "partially unavailable" - including card payments, transfers, ATM withdrawals and its customer support services to be having issues.
On social media, a number of users have criticised the company over the outage - saying it left them unable to access funds, make payments or contact customer support.
Revolut is one of a handful of so-called "neobanks" that sprung up to rival traditional banks.
According to its website, the bank has more than 80 million customers worldwide.