For the past month or so I’ve been seeing unusually high drain on my iPhone 7 battery. Its left untouched when I’m at work with Wi-fi off and it’ll go from 100% to 30% over the course of 7 hours. I’m running iOS12 but have seen no change from when it was on iOS11. Battery health says it’s at 84% of its original maximum. I don’t really want to fork out for a new phone... might just need a battery case if there’s not a fix. Any thoughts / ideas are gladly welcomed.