I don’t know what to do next about CSA

I started paying CSa in1996 after I got in touch with them the agreement between me and them and the mother was 35£ aweek which I’ve paid for 18 years.

Paid for all school holidays all of his clothes had my son every weekend for 14 years anything he wants if affordable I buy still now and he’s 19.

I have worked it out at 54,000 pound been to court twice for liability orders no way of fighting it now they want more money there’s only half a story because don’t know what to do next.