Try this: Log into your device and change the name of one of the networks. Doesn't matter if it's the 2.4GHZ or the 5Ghz network. Then try connecting your devices to the 2.4GHz network.
my wireless printer will not pair with my router. It worked fine with my previous provider. Also, my garage door sensor will not pair.
Are you associating them with your home network's current WiFi broadcast name (SSID) and your WiFi network's current password / network security key ?