Hi, I am having my 3 pack X60 deco working well in my house - 3 storages where each floor I have a deco mesh point and all connected with cat6 ethernet cable. All working well, except in one of the room on my 3rd fIoor, far end of the mesh point on the 3rd floor, my iphone is always connecting to the 2nd floor 5G signal rather than the 2.4G signal from the 3rd floor mesh. The result is even though it is physically closer to the mesh on the 2nd floor, but because concrete floor disruption, 5G signal cannot even support normal youtube streaming. How I can setup the system without relocate the mesh? Just need 2.4G wifi for low quality youtube streaming.