i have reset the entire phone on multiple occasions which would effectively reset the network. It works the first time as it did this morning and then goes back to the same issue. I do not have this issue with any other bluetooth devices I have connected. My husband has the same set up and does not have these issues with his galaxy watch.
Rather than doing both at the same time, I just reset the phone and got no change. Then I reset the watch, (powered down and back up). Now it's connected. Based on history, I don't expect it will stay connected. I don't see this as a workable solution.
Again, battery life is better, even acceptable without the WiFi. My bigger concern is the bluetooth connection. It has been disconnected probably 90% of the times I try to sync to my phone. The process to get it reconnected is never easy. Usually takes two or three tries if it works at all, going between phone settings and the apps.
I have had this watch since day one. Prior to this I had the GearS3. While I had the GearS3 I learned that turing off the diagnostic information that Samsung receives saves the battery by about a day. I have done the same on Active 2 and I can get about 3 days out of it with bluetooth on.