"Honey, can you bring me the stepladder? Yeah, she's stuck in the air again."
The older girl in orange watches appraisingly as the tiny one in red floats 10 feet above the ground. Camera Manikov steps in for a closer look, making all of the noise in the world as he does so, and the girls spot him. The hovering child drops back down to earth and the two run off.
They would have flown off, but they'd expended their spell slots for the day.
Now, the obvious answer here is that the girl is on a wire. There's even a convenient gap in the filming -- as the guy is moving in closer, the camera is pointed at the ground for a second or two, and when it snaps back up, the little girl is already back on the ground. We don't ever actually see her descend, which if wires were involved would be a dead giveaway. You'd see her tilting awkwardly or her clothes pulling up at odd angles wherever the wires were attached, even if she were wearing a harness. So clearly, she's being held aloft by wires that are connected somewhere in the trees ...