My partner and myself are having problems with the CSA too. I dont know anyone that deals with them that doesnt have problems. My partner had a direct debit set up to pay his ex every month and they said he wasnt paying enough so put a deduction of earnings on him. We have a child together and they just cant get their sums right as they are now saying we owe them arrears and are taking between £500-700 every month! Weve written to them and called them and they know its wrong and they are "looking into it". My partners ex has had £6000 in a year! We went to the CAB but they got fobbed off by the CSA so we are now seeking legal advice and going to our MP,which is what I suggest you do if youve tried all other avenues. Good luck each and everyone of you