I purchased a used watch from a private buyer. Serial number is clean and says that it's able to be paired with a new device. However, when I attempt to pair the watch, it instructs me that I must update to the latest watch OS. Here's the problem... I keep getting the "charging with this accessory not supported by apple watch" error. I've used multiple chargers, multiple wall outlets and usb ports. Since the watch wont charge, it wont allow an OS update, and thus will not pair. Wondering if this is a common issue