Impossible to make zwift academy trainning or any trainning on Bkool smart pro 2

In a race the bkool works well but i dont know why on trainning its impossible to make a workout, the resistance is to high and cant reach easy watts is like to make a 500w effort on 250w also when im on high watts suddenly the resistance increase and is imposible to pedal.

Hi @Asier_Gandarias

Are you using ERG mode? Then this will be helpful https://zwiftinsider.com/erg-mode-in-zwift/