Where can I find help?

Well i have just found out the csa fraud benfit is looking into my case, but just dont no why.

What been happening my ex have been paying 65 a week for the last year then last november it just stopped so i phone the csa and they just he stopped working. Then a week in december i seen him in this work van what he been working for the last 10years and then i phone them back and told them and then in feb they side he would start paying again but still no money.

Then in march i had 3 letters saying he would pay but nothing and i had letter last we say he start paying april 4th but nothing and since feb.

I made 36 calls but all diffent adive gives me different storys so i gone all the letters together and put the name what is on the letter and googled it and it side csa fraud benfit so i just phone them back and they tryed to make out i didnt no what i am on about.

So please, if anyone can help me where can i go for help cause i am not doing anything wrong?!