Which king of Judah rebuilt the high places his father Hezekiah had destroyed?

Answer: Manasseh

Manasseh rebuilt the high places Hezekiah had destroyed, raised altars for Baal and made an Asherah pole, as Ahab had done.

“Manasseh was twelve years old when he became king, and he reigned in Jerusalem fifty-five years. His mother’s name was Hephzibah.”— 2 Kings 21:1 (BSB)