The National Disability Insurance Scheme (NDIS) is dedicating a team of more than 20 staff to resolve payment delays experienced by providers, after a number of concerns raised in the past six months.

There have been reports of practices closing because of delays in NDIS payments.

From January 29 to February 4, the NDIS indicated 21,810 payments had been unsuccessful, and 14,086 of those were because the "claim amount was greater than the available service booking".

National Disability Services chief executive Ken Baker, who represents the non-government sector, said delays were likely to be because a person's plan had expired and there was not a new plan in place, so there was not a booking against which a claim could be made.

South Australian speech pathologist and Dignity Party candidate Diana Bleby said she had been experiencing delays with NDIS claims for the past two years, and had gone without a wage occasionally to help manage the budget of her practice.

She said NDIS agencies were not following up with meetings to renew a client's plan after 12 months, and were instead providing an interim plan while the providers continued to offer therapy.

"Clients are given three-month interim plans and we have to wait until the gap in the program closes before we can claim for a session that was done three or four months ago," Ms Bleby said.

"You can never be guaranteed that a plan will continue at all … if you continue to provide services in a gap period, you run the risk of not getting paid.

"We've had in our practice 20 of those clients recently … we have plans outstanding between three and six months old."

Practices closing because of payment delays

Ms Bleby said that meant the practice was short more than $10,000, and she knew of small practices closing because they could no longer keep up with budgets due to NDIS payment delays.

When asked if she has been informed about the new national team, Ms Bleby said no.

"No one tells you that … where's the communication?" she said.

"I've had to create an admin position just to make sure we get paid."

Ken Baker says there are problems with the NDIS that will take time to resolve. ( Supplied: National Disability Services )

Mr Baker said delays with meetings to form new plans were most likely due to the high volume of people being introduced into the service.

"I think some of the systems and processes that were put in place for the trial have proved inadequate for a scheme that's going to support 450,000 people," he said.

But Mr Baker believed the issues were manageable over time.

"There's still some way to go before these problems are solved," he said.

In a statement to the ABC, a National Disability Insurance Agency spokesperson said a centralised provider payment team had been established as a single point of contact for providers experiencing payment challenges, and complaints could be made through a website.

Issues experienced by businesses have been raised numerous times in the past year, after a report found business confidence among disability services slumped by 10 per cent, 18 months into the transition to the NDIS.