NPower CEO Paul Massara has written an apology letter to domestic customers for service problems resulting from the installation of a new billing system.
In the letter, which is echoed by content on the company's website, Massara promises they will not lose out financially as a result.
NPower is also making a £1m payment to the NPower Health Through Warmth Scheme Crisis Fund, which supports vulnerable homeowners with cold-related illnesses.
Half of this money will be allocated to Macmillan Cancer Support, which has been the energy company’s corporate charity partner for nine years.