What's eating my leaf

First time grow got two plants in a tent and two outside, both outdoors are autoflowers they are side by side day and night one is ok the other got devoured today, any hints would be awesome didn't see any bugs on top or bottom of leaves. Any suggestions are welcome, thanks all

Preventative treatments …. Neem / Spinosad / etc.

Gilbert Grape?

Elephant autoflower if that's what you're asking , I've been looking for pure neem oil seems difficult to find in store in London ON, is spinosad the best alternative Or would a insecticidal soap be a better choice?