Leather belt essentially melted In the sun on my backseat, what do I do?

Title explains it, left a leather belt I’ve had for years on my back seat(cloth) and the sun melted a portion of it to the chair and a resin substance also creeped across the back seam of the seat leaving what looks like an oil spot as well as a gummy substance that can be scratched off and is almost like a fruit leather consistency.

A) Sorry my run on sentence, I’ve had the car for two months and I’m livid.

B) Any thoughts on how I should approach this?