hi danny,
Since in freelancing is different from employee / employer relationship, di mo malalapitan ang dole. the agreement is between you, a freelancer, independent professional and a company who contracted you to do a certain job. thus this is not suitable in the labor and employment thread. try to post this question in the contracts and obligation section.
Btw, if you got your freelance job in the freelance website, you can approach the admin and report the company. if not, try to contact the legal bodies in that company to file a complain. Next time, I suggest that you investigate first the company and have them pay down payment first before doing their request.