Advice please‼️‼️‼️

My ex sees our children saturday-sunday as its COURT ORDERED. He comes to my city to pickk up our kids on saturday I go to his city to pick them up on Sunday. My car recently broke down and I asked if the dad could pick and drop off in my city just for this weekend. He said no and I better figure it out on getting the kids or it’ll be child abandonment. So I pulled money out my utilities and got my car fixed and did an extension on one of my utilities no biggie.

Here’s the thing:

My ex had his mom text me saying he won’t be able to get the kids this weekend because he’s going to work and I need to keep the kids this weekend. I start my new job as I’m a nurse. My childcare is closed on the weekends. What can I do?