How can I collect past due child support that wasn't paid during a temporary order in GA?

We have had our final hearing and we are waiting for the final order to be sent. We had temporary hearings in which my ex agreed to pay 100.00 per week. Because the judge changed support as of June 1st my ex thinks he doesn't have to pay the previous order. My ex still has not paid anything for a month now. What can I do to get support for my daughter?