"Where is our taxi?"
Translation:Где наше такси?
It is the gender of a noun it refers to. Такси happens to be an indeclinable neuter noun, and a neuter nouns takes наше. Наш and наша are used for masculine and feminine nouns respectively.
I accidentally entered "неше" and it said it's correct, but I have a typo. Why does it accept the answer, when it's not correct, much less a word (according to a native I asked)? This seems to happen infrequently, but it gives me the green banner, instead of red, when it's highlighting a typo. If the word is wrong, it should be marked as incorrect.
Essentially, the same thing happened to me. I used "ноше" and it accepted my answer as correct.