Beleaguered energy supplier Npower said it was "making good progress" getting to the root cause of problems with its new billing system, despite accusations this lead to the dubious title of "most complained about energy provider".
Roger Hattam, director of domestic retail business for NPower insisted the firm is tackling its customer service problems.
We wrote to all our customers during this period last year apologising for the impact on them of issues we have had with the implementation of our new billing system.
We are making good progress in dealing with the root causes of this, but remain totally committed to resolving any problems this has created for our customers.
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