Use a T8 Torx screwdriver to remove the screw holding the spiral drive mechanism in place. This is the drive mechanism that spins the brush bar.

Use a thin flat device such as a spudger, screwdriver, or metal prying tool to lift the spiral drive piece off its axle.

You can now see one side of the ball bearing. This is where hair gets trapped if the brush bar is not cleaned regularly enough.

You can remove the hair and regrease the ball bearing from here.