Some sensors use bluetooh to know how close/far a user is, roomme is a good example of it, but works with devices like phones to do it job. But so often the public I will to apply it leave their phone on someplace while move to another place, so, does not work as expected.
Wyze sensors with brigde, for me, works well on very small places, but do not work as expected on small, medium and large places. So I would like to suggest the use of Bluetooth already builtin on Wyze band to accomplish this like roomme does today: https://www.intellithings.net/roomme