I have got this Duck stamp which is a prooper stamp with everything it has got as it should do, meanwhile I have got which seems to be printed with missing parts, any idea about it, why could have been left like it is?...
First, it appears that this is not a postage stamp, but a stamp necessary for use with a national park access pass. The second imperforate, undenominated stamp looks to be an essay proof, used for design and color demonstration
I would be patient in deciding what to do with it. Your thread has been posted here for only 1 hour. I'd give it at least a week. Depending on its legitimacy, it could have considerable value - or not.