You might have to break the CD and pull out the pieces with pliers or tweezers. That is if your CD player has an opening that you can fit pliers or tweezers into.
I looked it up and it’s still under warranty! Just barely, another few hundred miles and it wouldn’t be. Took it in to the dealer and they couldn’t get it out so they’re getting me a new one. They claimed blah, blah, cheap cd, don’t use, wrong format, bad for machine. Whatever, I’ve been using cheap home-burned cds forever and the problem wasn’t the playing ability but the eject button.