After 3 Years My Ex Husband Wants To Enforce Custody Agreement.

New Mexico USA. As the above says my ex husband wants to enforce our custody agreement after 3 years. We have a now 3yr old just the one child between us. He hasn’t paid child support in the 3 years as per the original custody agreement that was signed by a judge. He hasn’t paid anything, and only seen her a few times in the 3 years. I have text message proof he hasn’t contacted me in a year to get her or see her or even check and see how she’s doing. I did go to the court house today to file to reopen the case to enforce the child support as well as get full sole custody of her due to abandonment. NM law say 3 months of no contact it’s abandonment. I believe it was said on video Christmas Eve so 2 days ago, once he catches up on child support (3 years) then since we have current 50/50 custody he doesn’t have to pay it. But I know you have to pay till the child is 18 unless something else is required for it longer. He did say he will message me on Sunday to get her but I was told since he hasn’t reached out to me in a year on top of me filing to open the case again, I don’t actually have to give her to him. I would rather not because I have no idea how he is currently along with his wife. Do I have to let him see her? Will I get in trouble and or arrested for “kidnapping” if I don’t let him have her? I really have no idea about anything like this. I just want to make sure I’m doing the most I can for my child and protect her as much as possible.