Albert Barnes Commentary 2 Kings 13:3

"And the anger of Jehovah was kindled against Israel, and he delivered them into the hand of Hazael king of Syria, and into the hand of Benhadad the son of Hazael, continually." — 2 Kings 13:3 (ASV)

All their days - literally, “all the days.” This does not refer to “all the days” of the two Syrian kings, since Ben-hadad lost to Joash all the cities he had gained from Jehoahaz (2 Kings 13:25). Rather, it means either “all the days of Jehoahaz” (2 Kings 13:22) or “all the days of Hazael”—a period including both the time he led his own armies and the time they were led by his son.