Energy firms to pay back billions: Windfall for customers as Big Six finally agree to refund direct debit overpayments after pressure from the MoS/Mail on Sunday

People not always refunded credit on their account after switching provider Companies were making up to £36million a year in interest, MoS revealed Big Six conceded to repay customers and review accounts twice a year Energy Minister Greg Barker said news is a ‘real win for working people’