Not working AddForce in Character

I’m sorry. I wrote this article through a translator.

I set the Character Movement to Flying.
And shot Line Trace to the floor. If the distance is close, I applied upward force with Add Force. The character does not move unless the Add Movement Input is executed on the tick. (The Velocity is also displayed as 0,0,0. )
The Ai Controller is attached.

Can you tell me why?