What is the ruling if the parties dispute the nature of the commodity specified in the forward sale?

Primary text

If they disagree over the commodity, such as one party stating the contract was for one hundred sa' of wheat and the other for one hundred sa' of barley, both parties must take a mutual oath (tahalafu), and the contract is then dissolved (tafasakha) due to the inability to proceed. Al-Shafi'i, Abu Thawr, and the Companions of Opinion rule that this is analogous to a dispute over the price of a sold item.