Not A Bug Using Roost on a pure flying type causes it to temporarily be Normal type

[CatPokemonLego]

What type of bug are you reporting? Unsure

What is the bug?
SSBU theia body count was not working against clouds except for last turn, no clue what was going on for it
https://replay.pokemonshowdown.com/...-2123845291-g76x65j3scgka0zzwxgx44ak27e4z3fpw

Are you able to replicate it? If so, how?
0 clue on what was happening

 

[Irpachuza]

Corvisquire roosted on the turns you attacked it, making it Normal type until the turn ended. When they used Brave Bird they kept they mono Flying type and you were able to hit them with your Ghost type move.