Sophisticated scammers are exploiting the cost of living crisis by sending messages to people who are worried about soaring energy bills.
UK Finance, the banking trade body, urged people to be vigilant after noticing a rise in the number of "smishing," or SMS phishing, scams that aim to impersonate major energy companies.
Recipients are told that their energy supply has been switched to another provider and that they should set up a new direct debit.
It follows the collapse of 27 energy firms since August 2021, on the back of a spike in wholesale gas prices - a move that has pushed millions of households on to other providers.
Have you been sent one of these messages? Get in touch: mirror.money.saving@mirror.co.uk
Household energy bills will rise by almost £700 this year after Ofgem, the energy regulator, said earlier this month that it would lift the price cap by a record 55 per cent to £1,971.
Ofgem also said that it was aware fraudsters were impersonating it: "Scammers may sometimes contact you pretending to be from Ofgem.
"For example, a scammer might say they are from Ofgem and suggest you switch and then ask for your bank details.
"These are scams. Ofgem [does not] sell energy or ask for personal information."
Fraudsters are also targeting victims via email and phone calls. In one case, criminals pretended to be from Eon, an energy supplier, and told a customer they were eligible for an £85 refund.
The customer was told to click on a link that took them to a fake Eon login page that enabled the scammers to steal their personal details.
Eon said: "We never ask for personal information, like passwords, payment details or your address."
Two more firms Whoop Energy and Xcel Power ceased trading last week, affecting hundreds of customers.
A statement on the Whoop website said: "Whoop Energy is ceasing to trade. Ofgem, the energy regulator, is appointing a new supplier for its customers."
An Ofgem statement said: "In recent weeks there has been an unprecedented increase in global gas prices which is putting financial pressure on suppliers.
"Ofgem is working closely with government and industry to make sure customers continue to be protected this winter."
If you fall victim to a scam, here's what to do.
