Dunedin woman Linda Rickard received a shock when she went to check her bank account this week.
The account was empty, and she had the mortgage and power bill to pay.
But after contacting her bank, she discovered Telecom had taken $403 from the account to pay for her ex-husband's new business telephone.
"I couldn't believe it," she said.
Telecom had used an old phone account number to set up her ex-husband's new plumbing business line, she said.
That old account was paid through direct debit by their joint bank account, which was now Mrs Rickard's own account.
"When we split, I set up a new phone account and so did he. But now he has started up a new business, they have used the old phone account and taken money from my account."
Mrs Rickard said her ex-husband, Ross Rickard, had paid her the $403.
"I would have thought they [Telecom] would have just used a new account number for his business.
"Plenty of people split up . . . You've got to make sure all your direct debits have been cancelled."
Telecom spokeswoman Rebecca Earl said the company used the old phone account number because it had not been cancelled by Mr Rickard.
The direct debit was reactivated because it had never been cancelled.
The direct debit could only be cancelled by Mr Rickard.
Company records show the Telecom salesman had spoken to Mr Rickard at length about the service he wanted, but no discussion about payment had taken place.
She said a letter was sent to Mr Rickard which clearly showed the form of payment was through direct debit and to contact Telecom if he wanted this changed.
Mr Rickard said he had not received any correspondence from Telecom.
He had called it about not receiving a bill but was told to wait for the next bill to arrive on July 6.