Contradiction with 1 Kings 1:39
1 Kings 1:18 claims Solomon isn't king, but 1 Kings 1:39 describes his anointing as king.
1 Kings 1:39: And Zadok the priest took an horn of oil out of the tabernacle, and anointed Solomon. And they blew the trumpet; and all the people said, God save king Solomon.
Contradiction with 1 Chronicles 22:9-10
In 1 Kings 1:18, Solomon is not yet king, while 1 Chronicles 22:9-10 foretells Solomon's kingship.
1 Chronicles 22:9-10: Behold, a son shall be born to thee, who shall be a man of rest; and I will give him rest from all his enemies round about: for his name shall be Solomon, and I will give peace and quietness unto Israel in his days. [Solomon: that is, Peaceable]