Neutralization Zone still going after being replaced

TioTinker

Gamestate was as following:

My opponent had NZ and a Drifloom with 60 damage as active

I replaced Zone with Town Store and switched my active to Mew EX

Used Genome Hacking to copy Drifloom's Gust

Genome Hacking's Gust did 0 damage to Drifloom

Am I missing something or it's actually a bug?