All lights green but it wont connect to the internet

I have a Netgear Range Extender and it used to work perfectly fine but recently after switching the networks and factory resetting it all the lights are a steady green and everything says its connected and working but nothing loads its like there's no internet. I've factory reset it so many times and yet nothing has worked. Sometimes when I connect to the network it would restart its self as soon I connectcted (I know this because the lights would turn off or turn red).