Until the time a buyer and a seller do not depart from each other, they can annul the transaction. Also, if a buyer purchases an animal, he has the right to annul the transaction within three days. If for three days a buyer does not pay for a commodity he has bought and does not take possession of the commodity, then just as it was mentioned in Ruling 2134, the seller can annul the transaction.
However, a person who concludes a settlement with respect to something does not have the right to annul the settlement in these three cases. But, in case the other party to the settlement delays paying for the property over which the settlement was reached for a period that exceeds conventional norms, or if a condition is stipulated that, for example, the item will be given immediately but the other party does not fulfil this condition, then one can annul the settlement.
Similarly, in the other cases that were mentioned in the rulings (aḥkām) pertaining to buying and selling, one can also annul a settlement. Furthermore, in a case where one of the parties to a settlement has been cheated, if the settlement is concluded to resolve the dispute, he cannot annul the settlement. In fact, in settlements other than this, based on obligatory precaution, someone who has been cheated must not annul the transaction.