ひとりがじゃなかったです
火取蛾じゃなかったです
hitoriga ja nakattadesu

Noun
Desu Copula

The polite, past negative form of ひとりが

1. Wasn't a firefly moth.; Wasn't a moth that gathers around fire.

Past/Perfective
Negative
Polite
Casual Register
Usually Written in Kana