Vodafone has apologised after breaching the privacy of one of its customers.

The woman says her safety was put at risk when her protection order was breached after the company gave her ex-husband access to her phone account.

Amy, whose name has been changed as she did not want to be identified, says she's been a loyal Vodafone customer for around a decade. But she was horrified when they allowed her ex-husband to access her account.

Her ex-husband first contacted Vodafone in May 2015, and, as an authorised user, requested to change the woman's details.

Later that month when Amy was unable to access her account, she filed for a permanent protection order.

She rang the Telco, had her PIN changed, restricted access, and had a note made on her file.

But in January this year the woman's ex-husband was able to access her details again. That's because her old PIN could still be used, as it was only changed on one of three access levels of her account. The customer service rep also failed to read the note on her file.

"I knew he was probably going through my phone list and contacting numbers of people he didn't recognise and didn't know to find out who they are and verbally abuse them."

Amy says that should never have happened, and the Telecommunication Users Association agrees.

"These call centre reps are going to be trying to get through jobs as quickly as they can, so that's why they need to stop sometimes and think, 'Well this is a very serious situation. I need to deal with it and give it the time that it needs,'" says chief executive Craig Young.

In a statement Vodafone has apologised for the error. It says it has tightened internal procedures and is giving its customer service reps specific training.

Women's Refuge says there's a lesson to be learned.

"The worst-case scenario is that we have a woman wind up dead because of a breach like this, so it's our own personal responsibility as a society as a community to ensure that when somebody gives us this information we treat it with the utmost sensitivity," says spokesperson Rhonda Cox.

Amy says it could have ended badly in so many ways, and "if it happens to someone else, who knows?"

She says she reported the protection order breach to police, and Vodafone is assisting with their enquiries.

Newshub.