Contradiction with Genesis 6:19
While Genesis 7:14 says animals went into the ark by twos, Genesis 6:19 specifies taking two of every sort.
Genesis 6:19: And of every living thing of all flesh, two of every [sort] shalt thou bring into the ark, to keep [them] alive with thee; they shall be male and female.
Contradiction with Genesis 7:2-3
Genesis 7:14 mentions all animals entering the ark, whereas Genesis 7:2-3 specifies seven pairs of clean animals and pairs of others.
Genesis 7:2-3: Of every clean beast thou shalt take to thee by sevens, the male and his female: and of beasts that [are] not clean by two, the male and his female. [by sevens: Heb. seven seven]
Contradiction with Psalm 104:9
Genesis 7:14 involves the flood covering the earth, contradicting Psalm 104:9, which states that waters should not cover the earth again.
Psalm 104:9: Thou hast set a bound that they may not pass over; that they turn not again to cover the earth.
Contradiction with Genesis 9:11
Genesis 7:14 describes the flood, while Genesis 9:11 promises no future flood to destroy all flesh.
Genesis 9:11: And I will establish my covenant with you; neither shall all flesh be cut off any more by the waters of a flood; neither shall there any more be a flood to destroy the earth.
Contradiction with Job 38:8-11
Genesis 7:14 depicts a global covering of waters, whereas Job 38:8-11 describes limits set for the sea, preventing it from covering the earth.
Job 38:8-11: Or [who] shut up the sea with doors, when it brake forth, [as if] it had issued out of the womb?