• Curve's "Go Back in Time" feature allows you to change the account you pay with after you purchase something.

• It's a patent-pending technology the company is rolling out to users on Monday.

Ever have a situation where you pay on the wrong card and then have to spend time sending money from one bank account to the next?

That's a problem financial technology or fintech start-up Curve is trying to solve with the launch of its patent-pending time travel" feature on Monday.

Curve is a London, U.K.-based company that has an app which allows you to link all your bank cards to one MasterCard. The idea is to create a hub that can track spending across all your accounts, rather than using several different cards.

The company has been testing the app for the past year and currently has 50,000 sign ups, with 45,000 users on a waiting list. But now it is gearing up to launch the app officially with better features.

One of those is called "Go Back in Time", and allows users to switch the card used for a transaction even after the purchase was made within 14 days.

Curve Curve's "Go Back in Time" feature on display.

"The problem that we are trying to solve is that users sometimes use their wrong card or a different card because they don't' have the right card with them or don't have enough money in their main account. It's about trying to resolve friction," Shachar Bialick, CEO of Curve, told CNBC in an interview before the official announcement.

When you pay with something using the Curve card, the money comes from your bank and is paid to Curve. The start-up then pays money to the merchant. But because you've paid Curve, it allows you to switch the account which you paid from even after the transaction.

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