An investigation has been launched into the estimates Ovo Energy gave customers about how much energy they used during the winter of 2016-17.
Energy regulator Ofgem says it will examine whether Ovo breached rules relating to giving customers information that is “accurate, or based on a best estimate, complete, and not misleading”.
The problem with incorrect consumption figures is that it can lead to customers receiving inaccurate bills, annual statements and other important information.
This in turn can lead to households being unable to properly manage their accounts and deciding to switch based on incorrect information.
On the investigation, a spokesperson for Ovo Energy comments: "We have a great track record in customer service and are always open to ways to improve it."
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