aggro female with male

[Kanej]

Hi there I have a 1.3 year old female veiled and a 9 month old male veiled. I am trying to get them to mate but she just hisses and bites but ahead stays a light green and he shows of all his colours. BuT I know that this happens I must separate them for two weeks then 're introduce them. Two weeks later and she still not interested. This has been going on for about 2 months.
What should I do??