In Ezekiel 26, it says that King Nebuchadnezzar destroyed the city of Tyre, but history records that it was Alexander the Great who conquered it.

“...therefore thus says the Lord God: Behold, I am against you, O Tyre, and will bring up many nations against you, as the sea brings up its waves. They shall destroy the walls of Tyre and break down her towers, and I will scrape her soil from her and make her a bare rock. She shall be in the midst of the sea a place for the spreading of nets, for I have spoken, declares the Lord God. And she shall become plunder for the nations, and her daughters on the mainland shall be killed by the sword. Then they will know that I am the Lord.

“For thus says the Lord God: Behold, I will bring against Tyre from the north Nebuchadnezzar king of Babylon, king of kings, with horses and chariots, and with horsemen and a host of many soldiers.  He will kill with the sword your daughters on the mainland. He will set up a siege wall against you and throw up a mound against you, and raise a roof of shields against you. He will direct the shock of his battering rams against your walls, and with his axes he will break down your towers. His horses will be so many that their dust will cover you. Your walls will shake at the noise of the horsemen and wagons and chariots, when he enters your gates as men enter a city that has been breached. With the hoofs of his horses he will trample all your streets. He will kill your people with the sword, and your mighty pillars will fall to the ground. They will plunder your riches and loot your merchandise. They will break down your walls and destroy your pleasant houses. Your stones and timber and soil they will cast into the midst of the waters. And I will stop the music of your songs, and the sound of your lyres shall be heard no more. I will make you a bare rock. You shall be a place for the spreading of nets. You shall never be rebuilt, for I am the Lord; I have spoken, declares the Lord God. (Ezekiel 26:3-14)

This is not an unfulfilled prophecy but one that was fulfilled exactly as it was written. First of all notice that in Ezekiel 26:3 it says that the Lord would bring many nations against Tyre. Not just one. It was in fact Nebuchadnezzar who destroyed part of Tyre; the coastal cities to be exact, but the residents at the port of Tyre fled to the nearby island city which they were able to defend against their Babylonian attackers. History records that just as it is written, many nations came against the city of Tyre, but it was Alexander the Great in 332 B.C. who finally conquered the city and left it in ruins so that it was never rebuilt.