My Ex Is Refusing To Let Me See My Children

Now before I start I will say that yes I’m currently filing out all the paperwork to get custody of my children. My ex and I split up a few months ago and the children were solely under my care. I was allowing him to get the kids over the weekend without a court order. Recently he went out of his way to pick up the children from school and is now refusing to let me see them. This has gone on for a few weeks. Within those weeks my children haven’t been to school either. I contacted the school, police and CPS, pretty much no one cares. Before we split up we had a car we got together in 2022 that was under both our names. Now he’s threatening to not let me speak to my children on the phone if I don’t take it in to get refinanced and put under only his name. This situation has me very tense and honestly angry. His mom bought him a cash car after we broke up and I’m guessing it’s giving him problems which is why he wants this car. Also yes he did agree to let me take the car that was under both our names so I could get our kids to and from school. This is messing with me and I’d just like a bit of direction on this….