I have a new LG smart tv on which I have no cable, just an antenna and Firestick. Up until a day ago I got about 18 channels, crystal clear, no problem. Now no matter what I do, when I scan for channels I get only 4 (cw channels 18.1, 18.2, 18.3 and 18.4); no abc, nbc, cbs, nothing. I an in...