I m having the slow wifi on 2.4 ghz and 5ghz working fine 

almost 7 to 10 device are connected on 2.4ghz and its give me speed fluctuation i tried  all method but its not working for me 

Kindly Help

@Abdulwahab there's an app on Play Store called "Netgear WiFi Analytics". Download it and see how many routers are connected to which channel. Then go in to the router's configuration page and select the channel (from 1 to 13) that has the fewest routers connected on. (for an example:4 routers are connected to the channel 7 and 1 router is connected to the channel 2. You have to set your router to channel 2 because it's the freest channel) Then set the channel's width to 40 mhz. If this doesn't work for you, try changing router's position. My router was between two old speakers, then I moved it on a table. My wifi speed increased from 100 mbps to 350 mbps on the 5ghz band and from 60 mbps to 100 mbps constantly on the 2.4ghz band. I hope one of those two methods will work for you! I hope I'm not wrong.