Jigglypuff was sleeping.

Jigglypuff is characterized by its sassy attitude and love of attention. In The Song of Jigglypuff, it secretly attacked Pikachu as an envious response to Ash's affection for his Pokémon. Jigglypuff is known for being a very heavy sleep. You probably don’t wanna touch her when she starts to sleep, or you’ll be sent flying.