We check all devices before shipping, unfortunately it can still happen that a sensor can loosen due to transport or by dropping the device.
However, there is no reason to worry. The device itself is not damaged by this. The advantage of the air-Q is that you can exchange the sensors yourself using a modular plug-in system or expand them later. The software then recognizes itself which sensors are equipped.
You can easily solve the problem with the loose sensors yourself by using the plug-in system, if you are confident enough to do so. In the following video it is explained to you exactly: