Arrears After Dropping Child Support

My question involves child support in the State of: Nevada
I had a child support case opened in CA but I moved to Nevada. I always thought that when you dropped child support that they still owed you back pay? I called the D.A.'s office to drop my case and they said that my ex no longer owes me anything. what excatly are the regulations when dropping child support?
I dropped my case because my ex doesnt visit or call my son. I only got child support once in a while and that was only when he worked. My bf is the one who supports my son and our daughter. I understand that it is not his responsibility or obligation in the case regarding my son but he loves him as his own. Is there a possibility I can get the back pay of support? The laws are different in ca and nv.

I have no way of investigating what you signed in relation to "dropping" support, nor of verifying what they told you. It may be that you signed something agreeing to drop the arrears along with the ongoing support obligation. It may be that you didn't drop the arrears, but that the documentation was not processed correctly. It may be that they didn't tell you, "You waived the arrears", but instead told you that by waiving support it's now up to you to collect your own arrears. Or... it could be something else. As we have no access to the records, and no ability to talk to anybody on your behalf, we're not going to be able to investigate this for you.