Thousands of electricity customers could be in for a shock because energy companies have not updated their pre-payment meters, it has been claimed.
The old-style devices needed manual calibration to ensure the correct price for electricity was being charged, however the news provider claims that the practice has not been commonplace.
Energy minister Ed Miliband told the paper: "I am disappointed that some of the energy companies are allowing their customers on pre-payment meters - many of whom are struggling to make ends meet - to fall into debt over an extended period."
He added that all energy companies should ensure that the poorest people in society are not landed with large backpayment bills which they cannot meet.
According to myfinances.co.uk, anyone wanting to change from a pre-pay meter to a standard meter should contact their energy supplier.
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