That's a great question. It sounds like this is a security code for using the watch. Is that right? If you have nothing on it that you care about (or if everything is backed up), you can do a factory reset. Here's instructions: https://www.verizon.com/support/knowledge-base-219178/. Otherwise, please contact the manufacturer, Samsung, at 800-726-7864 or http://www.samsung.com/us/support/contact to see if they have another way to reset or recover your passcode.