Contradiction with Genesis 11:12
Contradicts by providing a different genealogy that doesn't mention Mahalaleel begetting Jared.
Genesis 11:12: And Arphaxad lived five and thirty years, and begat Salah:
Contradiction with Genesis 6:3
Contradicts the long lifespans mentioned in Genesis 5:15 by limiting man's age to 120 years.
Genesis 6:3: And the LORD said, My spirit shall not always strive with man, for that he also [is] flesh: yet his days shall be an hundred and twenty years.