A:Answer Maybe you got a dud, but I'd try the following.
1: Try turning both off and fully charging the case/buds in the case through a usb port (do they both light up when in the charging case?)
2: Try turning them on again, after they come on it takes a few seconds for them to say they are paired (you'll hear it audibly in the ear piece).
3: If that doesn't work, try holding the button down for 30s or longer on the non working earbud
4: Return them for an exchange if all else fails