I have 2 devices (Philips TV & DELL Laptop) at home which only connects to 2.4GHz signal. And the problem now is, at random times in a day both the said devices disconnect from WiFi and wont connect for certain amount of time (hours in somecases) no matter what I try. I have to wait for the issue to fix by itself and then only I can connect my devices again. My devices are able to detect the wifi signal, but when trying to make connection it shows “Couldn’t connect, please try again”.
Question 1: Is there a way for me to check if 2.4GHz signal is up and running? 

Question 2: Is there a possibility to turn off 2.4GHz signal? so that I can check if my devices operate on 5GHz signal?