AirPods no sound

Start by checking if it’s because the volume is unbalanced If your left or right AirPod isn't working - Apple Support (CA)

If it’s not that, do you have another device to connect to so you can see whether the issue is with the AirPods or just your current device?

Also just in case - be sure you do a factory reset and not just a restart Unpair, restart, or reset your AirPods - Apple Support (CA)

Are they new? Possibly depending on where and what country you bought them in, you might still have warranty.

Either way, I would suggest bringing it into an Apple Store to see what they can do. There is a possibility they could replace or repair for you.