Are both TVs working off the same aerial ?
If they are trying tuning the non working TV while it is plugged into the working TVs aerial socket.
The signal could be weaker at one socket.
Also look for the signal strength in the TV menu.
If this is low you might not be able to retune.
If it is low, try checking at different times of the day.
It might improve at certain times. Try retuning the TV when the signal has improved.
If they are trying tuning the non working TV while it is plugged into the working TVs aerial socket.
The signal could be weaker at one socket.
Also look for the signal strength in the TV menu.
If this is low you might not be able to retune.
If it is low, try checking at different times of the day.
It might improve at certain times. Try retuning the TV when the signal has improved.