Fraudsters are targeting high-end London eateries and requesting that they call a supplied number to have every customer verify their payment-card details before any transaction gets authorized. Fraudsters may pretend that fraud has been spotted on a consumer’s account, or that a restaurant’s card payment system having a problem, as in the case of the recent London restaurant scam attacks. This type of social-engineering campaign is known as voice phishing, or vishing, which refers simply to criminals phoning people and pretending to be someone they’re not.”]
Source: https://www.bankinfosecurity.com/fraudsters-target-london-restaurants-a-7193