Gas and electricity provider Bluegreen Energy Services Limited has collapsed into administration.
The energy firm has around 5,900 domestic customers and a small number of non-domestic customers, all of whom will now be switched over to a new supplier.
Under Ofgem’s safety net, customers’ energy supplies will continue and funds that domestic customers have paid into their accounts will be protected, where they are in credit.
Domestic customers will also be protected by the energy price cap when being switched to a new supplier. That means they will be switched onto the provider’s standard variable tariff.
Ofgem will now assign a new supplier for all households affected, although this typically takes seven working days.

Until then, customers are encouraged to take a meter reading and wait for the new supplier to get in contact.
In recent weeks there has been an unprecedented increase in global gas prices which is putting financial pressure on suppliers.
A total of fifteen suppliers have collapsed since August following a 250% rise in wholesale prices.
Neil Lawrence, director of retail at Ofgem, said: “Ofgem’s number one priority is to protect customers. We know this is a worrying time for many people and news of a supplier going out of business can be unsettling.
“I want to reassure affected customers that they do not need to worry: under our safety net we’ll make sure your energy supplies continue. If you have credit on your account the funds you have paid in are protected and you will not lose the money that is owed to you.
“Ofgem will choose a new supplier for you and while we are doing this our advice is to wait until we appoint a new supplier and do not switch in the meantime. You can rely on your energy supply as normal. We will update you when we have chosen a new supplier, who will then get in touch about your tariff.
“Any customer concerned about paying their energy bill should contact their supplier to access the range of support that is available."
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