Josiah became the father of Jeconiah and his brothers, at the time of the deportation to Babylon.

After the deportation to Babylon: Jeconiah became the father of Shealtiel, and Shealtiel the father of Zerubbabel.

So all the generations from Abraham to David are fourteen generations; from David to the deportation to Babylon, fourteen generations; and from the deportation to Babylon to the Messiah, fourteen generations.