Greedy CSA take extra payments despite private arrangement with ex

So I was told my payments were getting moved to collect and pay I asked why and they said I owed a lot of money to my knowledge I owed none, they stated my arrears was £190 and because I didn’t set a standing order directly to them they added collect and pay charges on which no one informed me of I paid direct to my daughters useless mother now they have added a total of £600 charges to my account.

They are taking £240 a month from my wages and won’t stop it this child clmaintenance is a joke and won’t even help me sort this out they have made me quit my job now I have no way to support my 2 other children at home because of their greed.