This Bible contradiction is from the Skeptic's Annotated Bible.
He was Josiah's son.
Matthew 1:11 View context
And Josias begat Jechonias and his brethren, about the time they were carried away to Babylon:
He was Josiah's grandson.
1 Chronicles 3:15-16 View context
And the sons of Josiah [were], the firstborn Johanan, the second Jehoiakim, the third Zedekiah, the fourth Shallum.
And the sons of Jehoiakim: Jeconiah his son, Zedekiah his son.