Kindly refer to the following link(s):
Is hijab only cultural and not suited for this age and time?
Women who say "Allah has not guided me yet to do hijab" or "I'm not convinced yet"
Is a woman's prayer accepted if she does not cover outside?
Is not wearing the hijab a Major sin? Punishment for women who display themselves
Modesty (Hijab, Free Mixing, Punishment For Slandering, Perfume, Softening The Voice)
Women who barely cover their head and use make-up on TV
Modern hijab with jeans and a T-shirt?
Is not wearing hijab a continuous sin?