I am sorry you have tried all the troubleshooting steps to get this issue solved with your watch and the problem is still re-occurring. It sounds like a potential battery/motherboard issue to me if it is acting this way.
My suggestion is to call 1800-SAMSUNG (1800-726-7864). Once you call them, try to reach a representative and have the valid proof of purchase handy and the serial number of the device. Let them know you want to mail in the watch for service and they will email you a UPS shipping label and give you the proper instructions on how to do this process. It typically takes 7-14 business days for you to receive them back. The serial number and the proof of purchase is typically what is needed as long as the device was purchased less than a year ago. If it is out of warranty by date, they will charge you a fee to service it.
If you have any questions, please let us know.