Ring Doorbell 4 Battery Discharging Fast

Recently the battery in my Ring Doorbell 4 has been discharging to very low in about two weeks. I've reduced all of the motion settings etc etc but still the SOC drops like a stone. I have two batteries that I use in rotation, so its not one faulty battery.The only change I have recently made is changing my WiFi router in the house - can't see that this would create any problems.