As a result, Air NZ put a hold on inbound bookings until July 27, which it later extended until July 29.
Last night the airline told the Herald it has again extended the freeze on all new bookings for international flights coming into the country until August 9.
An Air NZ spokeswoman said this was to "help ensure the country is able to provide quarantine accommodation for inbound passengers for the required 14-day period".
She added other customers might also be affected.
"There may be a small number of customers who will need to be moved to other flights, and the airline will contact any affected customers."
Megan Woods, the minister in charge of quarantine and isolation facilities, said on July 7 the Government and Air NZ agreed to manage incoming bookings in the short term.
This would enable the Government to safely place New Zealanders arriving home into a managed isolation or quarantine facility, she said.
Woods said "we were never going to let" border facilities reach maximum capacity.
The freeze has caused problems for many Kiwis wanting to come home during the past month. When it was first announced a Kiwi stuck in Brisbane told the Herald he was scrambling to book an urgent flight to Auckland.
He spent a week looking for other ways to get home, including flights from other cities, but couldn't find anything and has had to wait until today - the first date that had been available when the freeze was first announced.
He is due to finally arrive today but other stranded Kiwis are likely to face the same nightmare as they wait two weeks for flights to become available.
Air NZ's website shows no available flights from major Australian cities until August 10.
Chief executive officer Greg Foran said the airline continued to work closely with the Government to support efforts to keep Covid-19 at the border.
"We recognise we play an important part in supporting the Government and New Zealand's fight against Covid-19," he said.
"Following this there is capacity for Kiwis to book flights to return home and we will continue to manage this going forward."
An All of Government response group spokeswoman said the Government was continuing to work with Air New Zealand and other airlines on the operation of the managed arrival system.
"Current data shows 3701 people are forecast to return to the country over the next seven days," she said.
"New Zealanders are returning home from all over the globe, and the Managed Isolation and Quarantine Unit is working with a range of agencies and partners to prepare for and manage demand and supply."
Woods last week said the existing system of 32 hotels across five cities was close to the maximum capacity that New Zealand could safely manage.
That capacity was for 7202 people, and with the intention not to exceed 90 per cent capacity to allow for some breathing space, about 15,000 returning Kiwis a month could be accommodated.
More than 30,000 people have passed through managed isolation and quarantine facilities since March 26.
Air NZ is operating a reduced number of international flights, something that is expected to remain in place until August 31, according to the airline's website.
Domestic services will continue to be scheduled to allow passengers to connect to Tasman and Pacific routes.