BD problems advice

Hi Ladies I really need advice I seperated from ex husband for 5-6 months we have a 2 year old together and he has been giving me less then he should be for child support now he is threatening me that he will quit his job and work under the table to not report him working so he wont give me anything for his baby what can I do.?

😔 ughhhh I did not make baby on my own and hes being a pos.!