Not sure what model of TV they installed but we have two of them in the house and one is on a antenna and the other is on Dish. Over the last 10 days I had the second one working on the antenna while Dish was making repairs to our system.
Had to go to menu then channel to air then scan. When I switched back to satellite I had to go menu then cable then tune to the set channel for the Dish network.
Make sure the antenna is up and turned on. Make sure cable is hooked into the TV.
We have a 28" in the craft room and 32" in the bedroom. Both work nice for the money. Neither are smart TV's.
Good luck
R.G. Miller