Can anyone tell me why I’m paying so much?

Can someone please tell me why the c.s.a are taking £220 a month off my wage and i am also paying £300 a month in a private agreement to another ex partner?

My issue is that in 97/98/99, the csa said that i was to pay £108.00 A WEEK for my child and i was earning £200 wages …. refusing to pay that absurd amount i was eventually only allowed to take home £80 a week wages and the csa took the rest … i was left with huge amount of arrears … i had 3 more kids with a new partner and we eventually divorced and she gets £300 a month without using the csa

i was paying £70 a month to the csa for years for first child and out of the blue they arrested my wages to the sum of £220p/m. in total now i am paying nearly 50% of my wage leaving just enough to pay my rent,electric and some shopping.

I am at my wits end, and understand that there is thousands of us in the same boat, phoning them direct is getting no answers, i pay that amount and that’s it. anyone help me with some solid information plz?