I want to pay less CSA to avoid claiming benefits

Hi, i want to move in with my girlfriend who is on benefits as she is a full time carer for her mum and i work full time and pay £104 a week csa for my twin boys who i don’t see.

I thought that she could stop getting benefits and i could pay the bills and the csa would take into consideration my ex wifes circumstances and see that she lives a great life and we would struggle if i still have to pay the full amount to the csa.

This is not fare both parties should be looked at as she works and does not pay tax and i pay far too much.please help us pay less csa so we can not claim benefits thankyou.