My sons childhood was stolen from me

by rodney
(arkansas)

My ex-wife wanted me to let her new husband adopt my son.I was young and stupid,so I let them. After signing the papers they told me it was done.They changed his name and went on with their lives. 15 years later she opens a child support case against me,and I find out she lied about the adoption. Now they say I owe $40,000 in child support. what can I do?