It could have been broken, stolen off or cut off. You should be able to see a plastic left over part between the tag bracket light and the frame. One time at Lake Powell (WahWeap) a British tourist was discovered with a suit case full of BASS Anglers license tags from their trailers. They just went through the lot with a pocket knife slicing them off. Park Rangers found them doing it one night to a trailer and then they searched their room. They found an assortment with one from every state they could get. Souvenirs!
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