Contradiction with 2 Samuel 24:24
This verse contradicts because it states that David insisted on buying the threshing floor at a price, whereas in 1 Chronicles 21:23, Ornan offers to give it to David for free.
2 Samuel 24:24: And the king said unto Araunah, Nay; but I will surely buy [it] of thee at a price: neither will I offer burnt offerings unto the LORD my God of that which doth cost me nothing. So David bought the threshingfloor and the oxen for fifty shekels of silver.