Apple Watch series 5

I am at a loss with this watch. The battery life if terrible. I have turned off everything possible. Apple even replaced it and the new one is just as awful. I have unpaired and paired. I have done the reset. I even took my phone back to factory setting thinking there was a software issue. My series 3 was amazing and I wish I had never traded it in for this one. I need the 18 hour battery life. I work really long days and I can't charge it in the middle of the day. Any suggestions? At this point I don't even want it if this is how it is going to be.