What did the Jews not metaken completely at purim (pertaining to amalek) that we still deal with amalek today?
One suggestion would be that the tikkun of destroying Amalek can only be complete by means of a king of Israel, and a true “war against Amalek,” as the Rambam sets out in his Laws of Kings (chap. 5). Another possibility is that although Haman was a scion of Amalek, he represented a leading figure within Amalek, rather than the entire nation of Amalek. He was done away with, but the general nation of Amalek remains after him, and it is yet to be destroyed.