So I had a problem where my watch would delete 90% of my contacts on just the watch (luckily not the phone too) and after receiving MUCH help from the Samsung Care Team, I just wanted to share how to fix it with all of you. We tried everything on the watch and nothing worked. The person helping me told me to go to the account settings in my phone (of course back everything up to it, first) and remove Samsung account from it, then add it again. So I did that, logged back in, and now my contacts are back on my watch! So for anyone having this issue, this may be the solution you need! Thanks Samsung!