Contradiction with Genesis 42:21
In Genesis 42:21, Joseph's brothers express guilt and fear over their previous actions against Joseph, which contrasts with Genesis 45:21 where they receive kindness and generosity from Joseph.
Genesis 42:21: And they said one to another, We [are] verily guilty concerning our brother, in that we saw the anguish of his soul, when he besought us, and we would not hear; therefore is this distress come upon us.
Contradiction with Genesis 37:24
This verse describes when Joseph was cast into a pit, an act of cruelty by his brothers, contradicting the benevolent treatment he provides them in Genesis 45:21.
Genesis 37:24: And they took him, and cast him into a pit: and the pit [was] empty, [there was] no water in it.