Ok, then your Digital Main board has failed.
The part number to fix your problem is --
That board has the input jacks on it, the tuner and the databus. Your micro isn't recognizing that you have a Digital tuner in it.
Now, we have a site that does provide the board --
And I know that they had a warehouse in the UK, but they merged the US and UK operations together.
I don't know if that affects shipping or not, but I do suggest you copy and paste that part number I gave you into Google, and see what sites are available in the UK first. Then choose the best overall shipping cost available to you, ok?
When you get the board, simply lay your TV on a padded table and remove the rear cover. Your cables and plugs have locks on them, so depress the lock and pull the plugs out. Then remove the screws holding the board to the frame, swap the boards, plug the plugs back in and screw it onto the frame.
Re-install the rear cover and you're done.
Re-Run the intial setup, or run the Auto Scan in the TV mode first, then the Auto Scan in the Digital mode next.
You should have both your analog and digital tuning back at that time.
If you have any questions, just ask
Tips are greatly appreciated !