Bassline303 (8/9/2020)
For me it looks like your hair hasn't been skin weighted as hair in CC3 but as accessory parented to a wrong bone. (but I am not sure too)
In the CC3 Scene manager you have symbols beside every mesh , which symbol does your hair have?Oh yeah, you're right. Hair as accessory might be parented to the hip bone and not the head.
Jordanlaboon -check to see what bone the hair accessory is attached to in CC3, it might very well be "Hip"...if so, you would want to change attachment to "Head"