Are Zigbee door sensors fit for purpose?

I’ve been trying to get a Sonoff Zigbee Door Sensor to work with a Sonoff ZB Bridge (using Zigbee2Tasmota)… I managed to get the sensor paired to the bridge, but it kept going offline. Using a tip from another forum I changed the channel of my wifi router to #6, but it hasn’t helped.
Now I can pair the sensor but I can’t get it to send any MQTT messages when I open/close it (it has done in the past).
Has anyone else had experience of Sonoff Zigbee Door Sensors? Is this unreliability common?