I have the Archer ax6000 router in the basement, a RE605X extender as mesh on the main floor and another RE605X on the second floor as an access point. Even if I am close to the access point on the second floor, the wifi signal is weak and my iphone keeps connecting me to the extender on the first floor. I checked the ethernet cable on the second floor that I am using to connect to the access point and I am getting close to one GB when I connect the cable to a PC. So the cable is not the problem. Any suggestions what might be going on and any advice to solve the problem?   Thanks