no rf signal detected

I have no idea what happened as this morning been working all Morning until 12 it stops working and WiFi symbol is solid green and the line below flashing light green, I have restarted the hub and I check cable and I got inside the hub and it say that no rf signal detected, no idea what it means or how to fix it, I try switch off WPS still no, i have restarted the hub like a new hub still no no idea what it means or how to fix i, I booked engineer to come in Thursday but really need now as my disabled son needs tablet to watch amd we have no internet in house at all, is there a way to get work before engineer come