The devices that were disconnected to the WiFi, are they connected to the 2.4GHz or 5GHz band network?   Not sure. I have configured my modem for band steering.  2.4GHz and 5GHz have the same SSID and same password. Hence, my devices connects to either.   Aside from rebooting the device, what other troubleshooting have you tried so far?   I have tried reserving an IP Address to the devices that normally having issues not connecting via their mac address. It does not help with the issue. But a restart of the modem fixes the issue of devices unable to connect. ... View more