Motion sensor 2nd Gen detects motion for no reason in conservatory

Recently exchanged my Yale alarm for a Ring Alarm system and the motion sensor in the conservatory keeps going off for no reason. The Yale system was over 10 years old and I never had an issue with the motion sensor in the conservatory which is in exactly same location. I have a Ring camera directly below the sensor, pointing in the same direction and that does not pick up any motion at the times the sensor does. Thinking the sensor was faulty got the supplier to swap it but the replacement is doing exactly the same. Looking at the time of day that it triggers it very much looks like it is connected with when the sun shines on the conservatory and thereby causing movement of air as it is warmed up. Definitely not spiders etc and does not happen during the night or when cloudy/overcast. Therefore has to be some sort of design fault as that should not be happening.