Never withhold visits with the kids because child support hasn’t been paid. These issues are determined separately. You cannot punish the non-paying parent by refusing visitation with the kids. What you can do is file a Motion to Show Cause and demonstrate how the opposing party is not complying with the Court’s order to pay child support. This paperwork is available in the clerk’s office. A hearing must take place. At the hearing, the party who is not complying with the order has an opportunity to be heard. If there is no reason why the order is not being followed, the Court may hold the non-complying party in contempt of court and impose sanctions.
You may also wish to have the Court issue a Wage Withholding Order so that the support money is sent directly to you from the other parent's employer.