My ex doesn’t pay any child maintenance at all, he rents out the rooms in his flat and doesn’t work, never has since we split so I get no maintenance at all, he also never has the children because of this so they are with me full time, he admits to me in my face that he has lodgers but never admits in messages etc, there is nothing I can do about this I’m guessing? I have no proof and if I did report him he says he would know it’s me anyway. Cms can’t do anything about this can they?