These AirPods Pro should still be covered under the AppleCare Manufacture warranty, which covers hardware defects and mechanical malfunctions. Depending on what the issue is, Apple may require payment to replace the broken unit, or will need to put a temporary hold for the cost of the replacement unit while they wait for you to send them the broken unit.
If you purchased AirPods Pro and want to check the warranty status, you can go ahead and check on Apple's website. Just search for "AppleCare Warranty Status" on Google (or your preferred search engine) and enter the serial number for your AirPods Pro. The Serial Number can be found on the inner lid of the AirPods Pro case or in the AirPods Pro settings in bluetooth. Enter the serial number in the text box and Apple will retrieve the status of the warranty.
Unfortunately, purchasing AppleCare+ for GeekSquad Certified Refurbished AirPods Pro is not an option.