Recently i bought Archer C6 V4 router.but i don't need 5GHz network. When i start the router, 2.4Ghz & 5GHz automatically on. I stop 5GHz network. But after some moments, 5GHz  automatically on again. I set wireless schedule, when it start automatically at 6am, both 2.4GHz and 5Ghz are turned on. But i need only 2.4 gHz.   I want to stop 5GHz until when it needs. What can i stop 5Ghz permanently????