Contradiction with 2 Kings 15:37
2 Kings 15:37 indicates that the LORD began to send Rezin the king of Syria and Pekah the son of Remaliah against Judah, while 2 Kings 16:5 mentions an unsuccessful attack on Ahaz, appearing contradictory in terms of the threat they posed.
2 Kings 15:37: In those days the LORD began to send against Judah Rezin the king of Syria, and Pekah the son of Remaliah.