I followed the steps but it's not working

I followed the steps, the light on the front blinks slowly several times and then is a steady white light but there's no picture. I've checked that the HDMI ports are working by pluggin in my cable box to them and the tv's input is on the correct input... I don't understand what that problem could be 😟 I have an LG 42LV4400-UA HDTV if that's helpful.

I also pluged the AppleTV into my computer and restored it in iTunes. Help!