[Solved] CSA

Hi. New to this site. And desperately looking for advice.

So 4 years ago I was seeing a lady and this went cold.
Once I'd finished it, roughly 3 months last she came to my door and was in pain so I took her to the hospital and they asked if she could be pregnant, I said no as she was on the pill and was also told she couldn't have children.
Any way she was pregnant.
At a meeting we had with her family I was told by both her mother and sister that she had stopped taking the pill in the hope to get pregnant and if I repeated it they would deny telling me.
I didn't want her to suffer so I get her money throughout her pregnancy for anything she needed or needed to stock up on.
But said from the start having the baby wouldn't bring us back together and I didn't want to be a dad. The relationship was toxic and she was controlling.
Her and her mother paid to get copis of my parents address and forced me into telling my parents or they would make a trip to them and tell them themselves. When he was born I was told either I go with her to sign the birth certificate or she'd put a court order that I did and due to the nature of my job I could not have any court orders against me.

She was finishing her university degree so I would do the night shifts to allow her to catch up on placement hours and complete her work. But I made it clear from the start I could do this for her and her son's future. I would work 12 hour shifts and do night shifts with the baby and then return to work for another 12 hour shift.

I paid her just shy of £400 a month via dd to support her and the baby for 18 months.
I then met my partner who questioned why we never had a light on in the house or why I moaned when she took too long in the shower or never had the heating on and I explained because of what I paid out I couldn't afford to heat the house or leave lights on. She went mad and told me to go through csa. Then when the mother text and asked for an extra £100 for nursery fees my partner said enough is enough.

Fast forward 3 years. My partner and I have a little boy and my partner has a 7 year old daughter. We live together and CSA are taking £500 out of my account when there letters state I should be paying £27 a week and they've added £4 a week collection fee. This is because I lost my job and when i found another I sent in the wage slips they wanted by they 'lost' them but the said they were photocopied wrong and couldnt read them. I was advised to cancel my DD by CSA while they recalculated it as they were still using my old (much higher) wage. My partner and I had our son prematurely back in Dec and we spent 4 weeks in TCU and it took some time to settle back in a home. So as you can imagine my priorities were not on CSA and chasing them up.

Then in April they took £500 out of my wages without notifying me. I rang and asked why and they said they'd look into it. Nothing came back until next month another £500. I rang again and made a complaint. They then after a 3rd excessive amount told me I was almost £2k in arrears and £800 in collection arrears!!!

My partner is on maternity and due back at work in Sept. I was told I had paid my arrears off and that my new payment would be £27 a week and then today just checked my bank and they've taken £400 AGAIN!!! We can't afford our mortgage this month, our outgoings even to feed ourselves and our children!!! Yet this woman work's 3 nights 's week, goes abroad 4 times a year and is driving around in her brand new BMW 4x4 and we've had to sell my partners car just to keep our heads above water.

What I am asking, is there anything CSA can do? Surely they cannot just take that money out knowing there areally 2 other children whow won't be able to eat this month? I was always told they took into account mortgage and any debts (there telling me 'no sir, we don't do this').

We as a family are athe breaking point and I really don't know what else to do. Can anyone offer any idea or support?