I can not legally provide you an answer tailored to your specific circumstances.
The general employment-based pathways to residence are:
There are other possibilities for gaining residency (e.g. new relationship with a New Zealander, Pacific Islander quotas), but they are far less likely to apply, and are probably not worth further elaboration.
If none of the above are options for you (and given that you mention that your employment is low skilled, there is a reasonable possibility that you may not meet any of the employment-based residency instructions), you may have little choice but to return to your country of origin.
You may want to engage the services of a licensed immigration adviser, who would be able to give you tailored advice and instructions with regards to a pathway towards residency, if such a pathway exists for you.