The Tynwald Commissioner for Administration says a Manx Utilities' response to a customer complaint was complacent, dismissive, discourteous and uninformative.
Paul Beckett was asked to investigate after a customer felt their complaint about the organisation's billing hadn't been dealt with properly.
He found a Manx Utilities internal report admitted shortcomings - but said there was a marked difference in tone and content in a letter sent to the complainant.
In a report due to be laid before Tynwald in October, Mr Beckett says a response from an MU director evidences maladministration.
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