Problem: Who was King Abijah’s mother? King Abijah’s mother was Micaiah, a different spelling of Maacah.
Solution: Maacah, 2 Chronicles 11:20, “And after her he took Maacah the daughter of Absalom, and she bore him Abijah, Attai, Ziza, and Shelomith.”
Micaiah, 2 Chronicles 13:2, “He reigned three years in Jerusalem; and his mother’s name was Micaiah the daughter of Uriel of Gibeah. And there was war between Abijah and Jeroboam.”
This is a very simple answer. Maacah was simply another spelling for Micaiah. They are one and the same.[1]
[1] Haley, Alleged Discrepancies of the Bible, p. 317, and Paul J. Achtemeier, Harper’s Bible Dictionary, San Francisco: Harper and Row, 1985.