Child support

I was ordered child support and full custody for both my children in Missouri. Neither their father nor I live in Missouri anymore, his address isn't current with the courts either even though he is on felony supervised probation in Missouri. He refuses to get a job so they cannot take any money out for child support and he hasn't had contact with kids in almost 2 years. Since child support was ordered he hasn't made a payment at all. Child support enforcement told me to wait until he is 12 months behind before I ask them to go after him since he is on probation. But since neither of us are in Missouri if I was to take him back to court asking for him to sign over rights or try to have him charged with abandonment do I do that in my current state? How does that work?