Hi Stephanie,
Sorry I was sick the other day, I'm a little better now so I'm able to get back on here.
Thanks for the additional information, If the LED on the case does not light up at all, please prioritize checking that the USB cable is connected tightly to the Surface Earbuds charging case. And if necessary, check that the other end of the USB cable is intact and connected to the computer's USB port or power adapter.
If, after testing multiple adapters, it still won't power the Surface Earbuds' charging case, then I have reason to suspect that the USB cable is bad.
It would be great if there were more USB cables that could be tested, because if it is noted that none of the USB cables are able to power the Surface Earbuds' charging case, then please negotiate a return or exchange with the seller as soon as possible.
Best Regards,
Mitchell | Microsoft Community Support Specialist