Question about Sample Asset's 2D character controller

Hi,

I'm making my game's character off of Sample Asset's 2D character controller (the robot guy) but there is a particular problem that I can't seem to solve by myself.

Whenever character jumps towards a wall and collides with it, it gets stuck for a second.

It gets worse if player presses the key towards the wall, it gets stuck there!

Any solution?

Thanks.