Battery drains in a day or less

When I first got my Vivoactive 4s, the battery lasted for about a week.  Suddenly, it would drain over about 6 hours.  I found some guidance about resetting it to factory settings and recharging, and it lasted for about 3 days.  Now, it lasts for about a day.  I don't know if any software updates had something to do with it, as I wasn't aware of the software levels from the beginning. 

Also, if I plug it into my computer a certain way, it keeps vibrating like it's connecting and immediately disconnecting over and over.  Is that normal?  I'm feeling like I need to return it, but I really like the watch other than the battery life problem.  If this is a problem with all of them, I'll look for another brand.  If there's a fix or this is an anomaly, I'd love to replace it with the same model.