CSA don’t know what they’re doing

I put in a claim for maintence back in 1999 and it took up till about 2009 for me to ever hear anything then that was with constant nagging always being on the phone to them. I eventually got awarded maintenance and they worked out a small amount of arrears which is currently sitting at over two grand but only got few payments then they stopped for over a year now the arrears seem to have been suspended for now what ever that means and they even had the check to take about 16 pound of one of my payments saying I was over paid when there is outstanding arrears they also sent a payment back to him as they received it a couple of days early what’s that all about this money is what he should have been giving his son all along he has never had anything from him where as his other children did its teaching my son that its okay to cheat and u don’t have to be responsible for the consequences.