The customers of telecommunications companies TalkTalk and Tiscali may be due a refund for bills charging them for services they never received. These problems stemmed from TalkTalk’s 2009 takeover of Tiscali.

Ofcom is pursuing an investigation after having received more than 1,000 complaints this year about the company’s billing. Ofcom has told the firm to refund those consumers who were being billed for services that they had had cancelled since January of this year.

One customer was ordered by TalkTalk to pay £610 for services cancelled four years ago. Another was contacted by debt collectors, who demanded £354 for a broadband account that had in fact been closed for over two years.

The firm is being told to cease debt collection and to withdraw from legal proceedings. It is to pay customers’ legal costs and repair the credit ratings of affected customers. Unless it manages this by December 2 it will be fined up to 10% of its turnover. This is a considerable amount for the company, which recorded sales of £1.39 billion last year.

Robert Hammond of Consumer Focus, a watchdog agency, said: “It is shocking that the intervention of the regulator or TalkTalk and Tiscali UK to play fair with their customers.”

A spokesman for the company issued an apology for the inconvenience it has caused customers.