VIzio channels won't change. We have had our new tv for about 6 months and this morning the

Question

We have had our new tv for about 6 months and this morning the channels won't change. What do we do?Mine did the same thing about two weeks ago. I've had it for 8 months and it's worked perfectly. Two weeks ago I was watching it during the day and everything was good. Came back that night and the channels wouldn't change unless I manually entered them and the HD channels wouldn't come in. The channel up/down doesn't even work on the TV. For a while if I switched it over to antenna, the channel up/down would work, but now that doesn't even work. Need some assistance - more than just unplugging it.