Haze not working during hidden stages of moves

I'm not sure if this is the right place for this report, sorry if it isn't.

I've been training some Pokemon in CC for a while and I realized something. Haze, which removes all stat changes, does not work during the hidden stage of the move "Fly" and this probably is the case with Dig and Dive as well. I'm fairly sure (not 100%) that Haze should eliminate stat changes regardless, correct me if I'm wrong. I didn't get a screenshot, but here's what pretty much happens.

Normal:

Wild Arbok appeared, go Charizard.

Charizard used Ember

Arbok used Haze

All stat changes were eliminated....

Charizard used Dragon Claw

Arbok has fainted.

_

Bug:

Wild Arbok appeared, go Charizard.

Charizard used Fly

Charizard flew up high!

Arbok used Haze... (turn ends and stats don't reset)^^^

Charizard used Fly

Arbok has fainted.

^^^= I'm sure of this because Arbok also uses Coil at times, and when I should be able to OHKO it with Fly after a Haze, I can't because the stat changes don't reset.