NTL again stands accused of trying to charge former customers for services they neither have or want.

Douglas and Gwendolen Harris, who are aged 84 and 82 respectively, were sent a bill for £103 months after writing to cancel their television service.

Mrs Harris insists she wrote on February 12 to cancel the £33-per month service, and wrote again when she received an erroneous bill.

However, ntl says it did not receive the initial letter for two months, that it did not receive a second letter, and blames the £103 demand on its automated computer billing system.

The couple who live in Haydon Wick are the latest in a long line of ntl customers, many of them senior citizens, who have been billed after cancelling their services.

Some, although not the Harrises, have had letters and telephone calls from ntl's debt collection agency, threatening damaged credit ratings.

Mrs Harris, a former civil servant, said: "What has happened here is absolutely disgusting.

"We had decided to change to Sky from ntl because my husband loves his sport channels. I wrote a letter on February 12, giving the month's notice specified in our contract and asking them to collect the ntl box.

"I then went to the bank and made arrangements to cancel our direct debit once the last payment had been made.

"We heard nothing from ntl, and then we had a bill for £68.

"I wrote again to ntl on April 9, explaining that we had given them the month's notice specified in our agreement with the company and that we expected them to honour their side of the agreement.

"We received no reply, but on April 15 we discovered that the service had been disconnected. We had our Sky system installed on April 24 and now we have received a £103 bill dated May 1."

Spokeswoman for ntl, Odette Sullivan, said: "We apologise to Mr and Mrs Harris for the stress and inconvenience we have caused them whilst they have been trying to disconnect from our services.''

She added that for some reason ntl had not received the couple's initial letter until April 14, and could find no trace of any other letter.

Ms Sullivan said the bills had kept coming in because the system was automated, but there would now be no more, and the ntl box would be collected on May 20.

She added: "We are very aware of the problems we have with the computer system used for the Swindon area to bill our customers and are currently two thirds of the way through a project to replace the antiquated system with a new one that will allow us more functionality.

"We have also changed our policy since mid-April so that customers no longer have to write in to ask for disconnection but can just phone us.

"Once again we apologise to Mr and Mrs Harris and have written to them today to let them know that we have resolved the matter."