Some of the UK's hottest fintech firms are currently down, including Monzo and Revolut

Ozone MonzoMonzoApp-only bank Monzo.

LONDON — A number of UK fintech startups encountered technical issues on Thursday, warning customers that their payments may not go through.

App-only banks and firms including Monzo, Revolut, Loot, and Curve have all run into problems due to a supplier that provides some of their underlying technology.

It’s not yet clear when the issue will be fixed.

Monzo, which does not operate any physical branches, currently offers its customers a pre-paid debit card, and plans to launch a current account. 

“Please take another card with you today — the Monzo card is currently being declined,” it warned in a push notification. “As you may have noticed, card payments, top ups and transfers have not been fully functional since 7:45 this morning. One of our suppliers is having issues and investigating as a high priority.”

Revolut is also reporting its supplier has technical problems. “Our payment processor is experiencing technical issues, which may cause card payments to fail. We’ll provide an update as soon as possible!” it wrote on Twitter.

 Curve, too, is warning its users of technical issues.

As is Loot:

A similar technical issue affected Monzo, Loot, Curve, and Revolut back in March 2017. Two sources told Business Insider that partner company Global Processing Services (GPS) is again behind the problem.

These outages aren’t unique to digital challenger banks. Barclays’ online services went down on the 3rd and 4th of July, according to monitoring service Down Detector. Nationwide also experienced technical issues on Wednesday, The Register reported.

Additional reporting by Oscar Williams-Grut.

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