Albert Barnes Commentary 2 Chronicles 29:1

"Hezekiah began to reign when he was five and twenty years old; and he reigned nine and twenty years in Jerusalem: and his mother`s name was Abijah, the daughter of Zechariah." — 2 Chronicles 29:1 (ASV)

The treatment of Hezekiah’s reign by the author of Chronicles is in marked contrast with that in the Book of Kings. The writer of Kings describes mainly civil affairs; the author of Chronicles gives a full account of Hezekiah’s religious reformation. Therefore, 2 Chronicles 29–31 contains material that is almost entirely new.