Paying tax on NZ proprty rental income

I've been living in Japan now for more than 10 years. I'm currently on a spousal visa though hope to transition to a permanent residence visa next year.

I own a house in NZ which I rent out and have for the last 5 or so years. I've been ignoring NZ when filing tax in Japan (meaning the return is taken care of by HR and I don't mention NZ). For the NZ income, I file a separate return in NZ for the NZ rental income.

My question is on tax. Is what I'm doing ok? Will anything change if I get permanet residency? And is there anything else I need to know about?

(I thought this was kosher but after talking with a friend who is putting off PR due to tax reasons, I'd like to learn moreand google searches haven't been very enlightening. Any NZers or Aussies out there who can shed some light on this, it'd be greatly appreciated!)

according to Japanese income law, you have to file your foreign incomes in Japan.
I advise you hire an accountant to correct it, because you are now doing tax evasion.

https://www.japan-guide.com/forum/quereadisplay.html?0+168263

The national tax authority has a definition of "permanent resident" for tax purposes. Please see the description in the link above to see if you need to declare all income worldwide to the Japanese authorities. This is not based on whether you are a permanent resident according to resident status.

Under NZ tax law, owning a property in NZ would make you tax resident there and liable for taxes on worldwide income a second time, but fortunately there is a "tie-break" in the taxation agreements.
With the tie-break you effectively become a non-resident for in NZ for tax purposes and you are required to pay tax in Japan on your world-wide income as a tax resident in Japan. (This is separate to status of residency.)
What you have been doing wasn't correct.