First of all. I recommend that you setup the router to broadcast only the 2.5GHZ band as the 5GHZ band struggles when there are walls or other objects in the line of sight of the router. Second, make sure you are connecting to YOUR router sometimes routers will come preset with a generic name. Example: NETGEAR, LINKSYS, ETC. I recommend you change the routers wireless broadcast name. Third. You might be out of reach of the router I recommend to purchase a extender to extend your signal downstairs.
Linksys - AC750 Boost Range Extender - White
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TP-Link - Wireless N300 Wi-Fi Range Extender with AC Passthrough - White
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Amped Wireless - High Power AC1200 Wi-Fi Range Extender - White
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