Battery Drain

Since the latest update iOS 14.4 my iPhone 6s battery drains really fast especially if I’m on a call. The battery health is at 92% and the phone is not yet 2 years old. I’ve turned everything off that may cause draining as per tips that are given but very frustrating. Fortunately I can charge it frequently as I’m stuck indoors (COVID lockdown) but if I needed it for an emergency whilst I’m out it’ll be useless. Not happy!