EDF Energy has acknowledged that its customers were caused significant disruption when the firm introduced a new IT system in 2011 and has publicly apologised for this.
Ofgem said that the firm's payment of £3 million to vulnerable customers was a "step in the right direction".
EDF Energy failed to have sufficiently robust processes in place when they introduced a new IT system and this led to the unacceptable handling of complaints.
Their commitment to putting things right and paying £3 million to the Citizens Advice Energy Best Deal Extra scheme and the Plymouth Citizen Advice Bureau's Debt Helpline to benefit vulnerable customers is a step in the right direction to rebuilding consumer trust.
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