There are stories that innocent people are asked to sign a piece of paper after inspection only to then be accused of dodging the TV fee so to be on the safe side I would rather lean to ignore their letters and refuse entry if they come in person and be done with it. Even if you can prove yourself to be innocent it still will take time and energy.
I myself made a mistake of trying to do the right thing, told them I do not need the licence on their website, then when I still kept receiving those infamous aggressive letters I called them to sort things out, obviously the person on the phone was utterly useless. So now I just occasionally receive those aggressive letters and sometimes they leave notes that they visited he property and nobody was in (they only try to visit when I am working and not at home). Makes me glad that they are wasting their time with those visits as I wasted time to make things right with them.
I myself made a mistake of trying to do the right thing, told them I do not need the licence on their website, then when I still kept receiving those infamous aggressive letters I called them to sort things out, obviously the person on the phone was utterly useless. So now I just occasionally receive those aggressive letters and sometimes they leave notes that they visited he property and nobody was in (they only try to visit when I am working and not at home). Makes me glad that they are wasting their time with those visits as I wasted time to make things right with them.