Reporting chain does not work

I bought this in 3 floors of our house to install the set of 5 wireless smoke detector. The establishment of the radio connection between the devices was easy, the radio link test before installing properly. Once the devices were permanently mounted, the radio link test no longer worked. Although the radio link between the individual devices was far below the specified range, the reporting chain between the devices no longer worked. For smoke detection, I can not say anything, I have not tested.