EDF have been found guilty of failing to properly record the complaints of its customers.
Industry regulator Ofcom found that EDF breached rules on customer complaints between October 2008 and March 2009 and subsequently launched an investigation, reports the BBC.
The energy provider was forced to make a £200,000 payment to charities which are dedicated to helping consumers.
"When Ofgem first identified in January 2009 that the number of complaints we had recorded was lower than expected, we immediately instigated a review and developed a robust action plan to resolve the matter," the company said.
EDF added that its actions led to an almost immediate improvement and its recorded complaints are now fully in line with industry regulations.
Under rules introduced in 2008, energy suppliers must record all complaints properly and have eight weeks to resolve any issue brought by customers. After this point, customers can take their dispute to the independent Energy Ombudsman.
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