A probe into energy giant EDF Energy's handling of consumer complaints by watchdog Ofgem followed a 30% increase in complaints when the firm began introducing a new IT system in 2011, the regulator said.
Between May 2011 and January 2012, EDF Energy did not have appropriate procedures in place to properly receive, record and process all customers' complaints in accordance with complaints handling rules, Ofgem found.
Many customers experienced unacceptably high call waiting times and there was evidence that the supplier failed to record all the required details for the complaints it received, the regulator said.
It said that EDF staff acted quickly to rectify the problems and to mitigate the effects on consumers.
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