The assistant beside the vip hairstylist. I tried both. I also tried dropping the coupon and repicking, logging off etc
@Noobaholic I think there's a mistake. Did you accidentally purchased the "Hair Color Coupon (REG)" instead of "Hairstyle Coupon (EXP)"? I'm bringing this up again because I accidentally bought the Hair Color coupon instead of the Hairstyle Coupon, which obviously makes sense as to why the NPC said I don't have the Hairstyle coupon, when trying to change my hair.
You know who I blame? The one who decided it's a good idea to name the hairstyle coupon as EXP, and hair dye coupon as REG.