You haven't given much information to go on, but if I may be the first to offer a sincere & constructive reply...
I wonder if it's because you're trying too hard, or perhaps she is shy or lacking in self esteem. Maybe she's looking to take advantage of you. Just a few possibilities that might be worth thinking about.
I would suggest you take a step back & review the types of women you court, ask yourself what you want from a relationship & see how that is matched by the women you are attracted to, then you might get a better understanding of what they are looking to get out of the relationship & why they put the amount of effort in that they do if you do go on to court them.