About a month ago, I noticed my 5gz capable devices were no longer connecting to my 5gz WiFi network.  My TP-LINK CR1900 (US) > Network Map > Basic >  SSID on 5gz and 2.4gz wireless networks are enabled as well as my 5Gz and 2.4gz Guest Network.  Under Advanced  > Status > Wireless Radio is ON for both 5gz and 2.4gz. My internet provider is Comcast > Infinity (Cable, not DSL),

My router shows both 5gz and 2.4gz wireless network are enabled and wireless radio are both ON and both my 2.4gz and 5gz SSID are showing listed on the available networks (including my neighbors) but the issue is when inputting my 5gz and 2.4gz SSID password(s), 2.4gz SSID works and 5gz SSID fail to connect.  I know I am entering the correct password and even tried pasting it, but it simply will not connect. I thought maybe my wireless card on my iMac and Macbook Pro are faulty so I recently purchased a TP-LINK Archer T3U Nano Wireless USB Adapter and that didin't help either.  My 5gz and 2.4gz wireless settings shows SSID name not hidden, WPA/WPA2 Personal (Recommended), WPA2/PSK, AES, and a strong PASSW0RD with 16 alphanumericalsymbol character. 2.4gz Guest and 5gz Guest are enabled and wirelss radio is ON, both are showing listed on the Network, but only 2.4gz enabled devices can connect to the router. 5gz enabled devices see my 5gz Guest SSID, but when inputting the password,it won't connect.  Rebooted router on numerous occasions and that didn't help either. 

I would appreciate a fix for this issue.  I can be reached by email at top3gearz@hotmail.com

Thank you,

G