Ex has never really paid cm, he hasn't worked since we split up so it's between £7 a week and nothing. He is currently paying 0 and cms don't know why but I suspect it's due to debts, it's a cycle for him, on benefits, gets into debts then doesn't have to pay and it just goes on repeat. However I know for a fact he is earning income through his property, I estimate it is around 3k a month as it is central London. Only he is not declaring this and I have no way to prove that it's happening (though I do know for sure as I've witnessed it and he has also told me verbally) I spoke to cms last week as he hasn't paid anything since November to find out why and they mentioned on the phone if I suspect he is earning on the side I can report it online. I looked and it seemed very simple however it didn't ask for any proof and I was told by someone they will go on what's being declared to HMRC so if he is not declaring it then it will come back as nothing? Is that right? At this point I'm ready to let him win and give up on cm. He doesn't pay it anyway and the arrears don't need to be repaid whilst he isn't working so the arrears mean nothing and are only going up very slowly due to it be £7 a month. Is it time to let this go or how can I make them take this unearned income into account if he isn't declaring it? Is it time to give up as I can't see any way to fight this and if it is even worth it? I will be closing the claim if I can't get anywhere with this.