I have given mount Seir to Esau - Though the descendants of Esau were conquered by David 2 Samuel 8:14, yet they were not dispossessed of their land, and in the reign of Jehoshaphat they regained their independence 2 Kings 8:20-22.
Related Commentaries of Deuteronomy 2:5
Deuteronomy 2:5
5 Meddle not with them; for I will not givea you of their land, no, not so much as a foot breadth; because I have given mount Seir unto Esau for a possession.