Ex won't support or provide for kids

I'm a single mum of 2 girls, I provide for them in every single way and my ex has only seen them 3 times in the last 9 months and each time has given me $100, those times his given money I've received text after text accusing me of spending it on my own benefits blah blah, when in reality I'm providing for my kids needs perfectly well without his help and do not need his money for my own things . I'd had enough of his accusations and we agreed that he would buy the kids what they needed (food, clothes) when he would take them out for the day. The weekend came and he took them for the day, he did not send them home with a single thing, he wouldn't even buy them lunch 🙄 . He is very manipulative, immature, selfish & narcissistic. I've tried to get through to him and make things easier for him, but he still always turns it around on me and would much rather argue. All my friends and family can see he isn't worried about the kids, it's just all me, I don't know how to deal with it anymore I've just had enough of raising babies on my own without his help, but when he comes around he still doesn't bother helping 😔