What do you do when a girl refuse to go out with you. But we had sexual relationship before.?

First of all, it doesn't matter what her job is you should always treat a woman with respect. Now, it seems as if she doesn't want to go out with you. Do you only want to be friends with this girl? Try telling her your hanging out as friends only. Or try laying low for a while, and after sometime if she still doesn't want to hang out with you then leave her alone for good.