Some users in the UK and other parts of Europe are experiencing problems paying for purchases with Visa cards for several hours now, as first spotted by Bloomberg today. It turns out Visa is experiencing a network failure, with the company now saying it’s investigating the issue. The company also confirmed on Twitter that there’s a service disruption in Europe.

The outage has caused several banks — including the Royal Bank of Scotland and the Bank of Ireland — to issue statements addressing the issue, noting alternative methods of payment that still work, like cash withdrawals through the ATM and Mastercard transactions. Still, in some places, Visa cards are working fine.

We are currently experiencing a service disruption which is preventing some Visa transactions in Europe from being processed. We are investigating the cause and working as quickly as possible to resolve the situation. We will keep you updated. — VisaNewsEurope (@VisaNewsEurope) June 1, 2018

According to The Guardian, some supermarkets are dealing with the problem by issuing paper slips to check out customers and many retailers are putting up cash only signs. When a user inserts a Visa card into a kiosk, the card issues a signal to Visa, but that’s where the error lies, supermarket chain Asda explained to The Guardian. The cash out feature on Visa cards appears to still be working.

Users who only have Visa cards in their wallet are left dealing with long lines at train station ticket counters and limited means of paying for purchases.