if the patent don't pay there child support but every other month what should I do , he has he self employed

It is unclear what the facts are, and there are some typos making it hard to know what you are trying to say ("nsck"?). For background as to the rules, and how arrears, interest and penalties are calculated, see http://willicklawgroup.com/child-support/.  For a more precise evaluation of what you can do, take all your paperwork, especially including exactly what was paid and when it was paid, to a family law specialist for a calculation under the MLAW Interest and Penalty Calculator, and for a consultation; if the sum is high enough, a motion to reduce arrears to judgment may be warranted, and there are (sometimes) automatic payment provisions that can be put into place to make child support payments more regular, even for folks who are self-employed.