The Island's Office of Fair Trading says it's working with Isle of Man Energy to resolve billing issues.
It comes following the company apologising to customers in October last year after 'teething problems' with its new billing system.
CEO Jo Cox wrote an open letter to personally apologise for any 'confusion or worry' the issues may have caused.
It meant some people didn't received a bill, had direct debits taken from accounts without getting corresponding invoices or didn't received any invoices for a considerable amount of time.
Now, government says as some, but not all complaints have been resolved - the matter has been escalated by the OFT.
A meeting held earlier this week determined there's a backlog of complaints that need to be cleared - with Isle of Man Energy committing do so in a matter of weeks.
The OFT says it has 'made it clear' to Isle of Man Energy that enforcement action will follow if this isn't done and will continue to work to resolve the matter 'as a priority'.
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