Haha, it's all good, and it gets fun when you hit the South Island / Te Waipounamu dialect of Māori where a maunga is a mauka, and sky is raki not rangi, but both variants are still used.

A classroom at my childrens' primary school was called Maungatere (floating mountain) after a nearby mountain which is now called Maukatere, same meaning.

Likewise the local iwi/tribe in my area is known both as Kāi Tahu and Ngāi Tahu, and there's a town in North Canterbury called Rangiora, which translates to, roughly "Good sky", while the 3rd largest island of Aotearoa New Zealand is called Rakiura / Stewart Island, Rakiura meaning "Glowing sky".

And our tallest mountain Aoraki / Mount Cook used to be Aorangi / Mount Cook.

And to be fair, "Mounga" is a decent rendition of how you pronounce "Maunga".