A similar question has already been answered here. It depends strongly on how many walls, etc. there are up to the 7th floor.
The manufacturer writes: "The reception range is up to 300 metres outdoors and up to 50 metres indoors. The reception range of the baby monitor changes depending on the environment and factors that cause signal attenuation. Wet and damp materials cause so much signal attenuation that
Further down in the downloads you will find the "Manual". There, information on signal attenuation is listed in a table.