A woman has been awarded nearly $85,000 because her employer used an invalid contract to force her to repay wages and then unjustifiably dismissed her.

Qishan Huang was on a work visa while working in Auckland for Independent Prosperity, which sells insurance products, between October 2016 and August 2018.

The Employment Relations Authority says the business director, Angela Churchill, demanded Ms Huang repay $22,000 dollars of salary and forgo 14 weeks' pay, because she had not met her sales target and had not covered her own salary.

It said Ms Churchill based her demands on a contract Ms Huang had not signed, and did not know existed until the document was filed with the Authority.

Ms Huang said she repaid the money - which she borrowed from her mother - out of fear of losing her work visa.

The authority said Ms Churchill's evidence was unreliable on a number of occasions.

"I do not accept Ms Churchill's evidence that the May and July [employment] agreements are not authentic, she had never seen them, and it is not her signature on those agreements," wrote the Authority member, Anna Fitzgibbon in her decision.

"Ms Churchill attempted to persuade the Authority, without any basis for doing so, that the signatures on the May and July agreements were not hers and that her signature had been forged," Ms Fitzgibbon stated. "This is one of a number of occasions in which I find Ms Churchill's evidence to be unreliable."

The Authority said "Ms Churchill says she issued two warnings on 5 and 6 March 2018 in relation to her performance. Ms Huang denies that she ever received warnings informing her that her employment was in jeopardy."

Ms Huang said Ms Churchill criticised her attendance at work, but Ms Huang said that was so she could develop client relationships.

In one of those emails Ms Churchill wrote: "It's your responsibility to control and avoid all the work visa risk and the responsibilities to achieve your yearly target, when or if the visa officer comes to do the research that will be also your obligations and responsibilities to fix up the incredible vulnerability [sic]".

Other staff gave evidence that they worked mainly outside of the offices premises, visiting clients.

"I have reviewed the emails ... and they do raise issues concerning Ms Huang's performance, but they do not constitute warnings that her employment may be in jeopardy if she does not meet Ms Churchill's expectations. Further, the emails do not set expectations for Ms Huang. Rather, they are statements concerning Ms Huang's supposed poor attendance rate," wrote the Authority member, Anna Fitzgibbon.

The $85,000 includes compensation for humiliation, loss of dignity and lost wages, as well as reimbursement.