A medical business at Kingston Beach is frustrated after works to rollout the NBN have seen its phone lines and internet cut leaving it unable to claim rebates for patients.

NBN infrastructure was installed at Kingston Beach Health centre but earlier this week, instead of being connected to the high speed network, it was left in the dark.

Practice manager Mel Baldock said she put in an order to have the NBN connected to the business more than a year ago.

But, she said, there was a problem in switching the phone lines of the business from copper to fibre.

"It's been a long drawn out process and we're at crisis point now," Ms Baldock said.

This week the business' connection to the copper network was cut.

Ms Baldock said the business was left without phone lines or a security alarm as a result.

"We can't accept any electronic payments, we can't take Medicare or private health fund rebates for people who are coming in for services," she said.

Sorry, this video has expired NBN frustrations fire up ( Fiona Blackwood )

Psychologist Tim Sanderson, who works at the practice, said the centre was unable to provide an adequate level of care.

"The whole point about being a health service is we're looking after people's health and wellbeing and it's just another problem that they have to solve and they have to deal with," he said.

The Australian Competition and Consumer Commission had previously given an assurance that customers with an NBN order would not have their copper lines disconnected until their fibre order was filled.

Telstra apologised and temporarily reconnected phone lines at the medical practice to the ISDN network.

Connection times 'biggest issue' with NBN

Dean Winter from TasICT said the regulations around disconnection from the copper network were too rigid.

"There needs to be more flexibility in an emergency situation," he said.

"Where businesses or households are unable to get an internet connection there should be an ability for them to go back onto the old copper network."

He said while disconnection was not a widespread problem, the speed of the roll out was.

Workers at Kingston Beach Health Centre are left frustrated after they were left without an internet connection. ( ABC News: Fiona Blackwood )

"Connection times in Tasmania are still really slow and it's the biggest issue with the NBN rollout at the moment," Mr Winter said.

"Essentially it's taking around three months on average for households and businesses to get connected to the NBN."

Andrew Wilson runs a shared office space in Hobart and said he first made an inquiry about connecting to the NBN about 18 months ago.

"Even yesterday I got a message saying that the building was live and when I called a service provider they said some of the rooms are available but not all of them," he said.

He said the delay was affecting his business.

"It's frustrating because no one can give you a straight answer and I think that's really hard for business because," Mr Wilson said.

"You can't forecast for future growth and take opportunities that might be there"

NBN Co said it was working with the business' retail provider to solve the problem.

It said in most cases it took about 28 days to make the connection to the NBN but complex sites could take longer.