New Zealand operator Spark was fined NZD675,000 ($454,536) for making false or misleading claims in customer bills, breaching the country’s fair trading act.

The operator admitted guilt in November 2018, after the New Zealand Commerce Commission (NZCC) took legal action.

In a statement, Spark said the billing issue related to a 30-day notice period for departing customers, and the incorrect implementation of a NZD100 credit for customers signing-up for its fibre broadband service.

The incidents occurred between June 2014 and December 2017.

A judge said the billing issue required commercial penalties, but accepted Spark’s conduct over the fibre credit was simply an error of omission.

In addition to the fine, NZCC issued a warning to Spark regarding a failure to correctly apply a NZD300 welcome credit to the accounts of eligible customers.

The billing problem resulted in nearly 72,000 customers overpaying by a total of NZD6.6 million, NZCC commissioner Anna Rawlings noted.

“Spark failed to take necessary steps to ensure its invoices were accurate. More than 7,000 customers still remain out of pocket despite refunds being made to a large number of others who were affected.”

“It is vital businesses clearly disclose the terms of any offers made when marketing their products.”

Spark said it fully cooperated with the commission about the incidents, which it claimed resulted from mistakes with no malicious intent. In a statement it said it “sincerely regrets the impact on customers and has taken all practicable steps to refund those customers who were billed incorrectly or did not receive their welcome credit”.

It said the outcome of the case does not impact its fiscal 2019 guidance.