Some of you may have this problem even though this issue is older than 11 months. This could be related to some of the devices, which you have connected to your network, which has running DHCP server. If the router detects any other running DHCP server, it will turn off the DHCP server, which is running on the router. That’s why you can experience this problem. So, the potential fix for this issue might be to disable running DHCP server on the device, which has it enabled.