She came from India as an international student at the age of 19 eight years ago with dreams of becoming a Kiwi and starting a new life here.

However, Sia (not her real name), says failed attempts to get her residency by her immigration advisers and lawyers has turned her into an overstayer - living here secretly since 2018.

Speaking to the Herald on the condition that she is not identified, Sia says she - like many Indian nationals living here unlawfully - came over on borrowed money, and had little choice but do everything they could to remain.

A former immigration minister is calling for an overhaul of the immigration system, saying the current student visa residency pathway has put many into vulnerable positions.

It is estimated there are over 10,000 overstayers living under the radar in New Zealand. Although most of them are from the Pacific Islands, a significant number are believed to be Indian nationals who came here first as international students.

"My family sent me over with the hope that I can get a better life, and I have spent over $100,000 including more than $30,000 on fees to immigration agents and lawyers, how can I just go back?" Sia said,

"I hope INZ will me another chance to live here lawfully."

After the election, Sia is planning to fly to Parliament to plead with the new Government to give her and other overstayers pathways to residency.

Sia said it has been a harrowing experience living the life of an overstayer.

"You just don't know who you can trust. People know you're vulnerable, so everyone just tries to take advantage of you," Sia said.

After running out of money, Sia was referred by an acquaintance to a cleaning company who offered under-the-table cash-paying jobs.

"The manager said I had to go with him one evening to see the sites to clean, but while in the car he tried to hold my hands and made sexual propositions," she said.

"It's really distressing, but people do these things because they know there is no chance I will go to the authorities because I'm an overstayer."

Sia arrived in New Zealand in December 2012 as an international student studying a level 5 business diploma course.

She claimed bungles made by multiple immigration advisers and lawyers she engaged resulted in her becoming an overstayer in 2018.

"I have been struggling since. I've spent all my savings, worry every day about being deported and having to live on charity and the kindness of friends," she said.

"I have learned not to trust anybody. Everyone just wants to exploit you."

Tuariki Delamere, an immigration adviser who Sia has recently approached for help, had advised her that she has no pathway to residency except to make a section 61 request.

Delamere, a former immigration minister, is standing as a candidate for The Opportunities Party this election. He is calling on the Government to re-look student visas when the borders are reopened.

Delamere says the pathway to residency was scrapped for level 5 and 6 diploma students, and offered to only those who graduate from higher tertiary levels.

"The current system has brought many here with the misguided belief that they can get residency, and this has resulted with many ending up becoming easy victims for exploitation," Delamere said.

An INZ spokeswoman said Sia was issued an interim visa on Aug 4, 2018, but her application for a work visa was withdrawn on Oct 2 after the agency raised a number of concerns about her employment.

She then remained unlawfully in NZ since her interim visa expired on Oct 23, 2018.

Sia had made several requests under section 61 of the Immigration Act for a student and work visa between November that year and June last year, but none were granted.

She then made a request for Ministerial intervention in July 2019 but a delegated decision maker (DDM) declined to intervene and advised her to depart before being served a deportation order.

A second request for intervention in July this year in the midst of the pandemic was also declined by a different DDM, and she was advised to make plans to leave at the earliest opportunity.

"There is an express obligation under the Immigration Act 2009 for all unlawful people to leave New Zealand. People who are unlawfully in New Zealand are expected to leave New Zealand or face deportation," the spokeswoman said.

People who are unlawfully in NZ are encouraged to contact INZ to discuss their circumstances and determine what the best options are for them.