Contradiction with 1 Samuel 6:19
1 Chronicles 15:15 describes the Levites successfully transporting the ark according to God's command, whereas 1 Samuel 6:19 speaks of the Lord striking down people for looking into the ark, indicating a handling of the ark that was not according to the commanded regulation.
1 Samuel 6:19: And he smote the men of Bethshemesh, because they had looked into the ark of the LORD, even he smote of the people fifty thousand and threescore and ten men: and the people lamented, because the LORD had smitten [many] of the people with a great slaughter.
Contradiction with 1 Chronicles 13:10
1 Chronicles 15:15 emphasizes following God's instructions in moving the ark with Levites using poles, whereas 1 Chronicles 13:10 mentions Uzzah being struck down by God for touching the ark, due to not transporting it as instructed.
1 Chronicles 13:10: And the anger of the LORD was kindled against Uzza, and he smote him, because he put his hand to the ark: and there he died before God.