What is incumbent upon one who doubts the order of the Jamarat stoning on the second and third days of Hajj?

Throwing the pebbles is obligatory, and for its validity, the order must be observed (first the Jamrat al-Sughra, then the Jamrat al-Wusta, then Jamrat al-Aqaba). Whoever reverses this order has not fulfilled the requirement. If someone reverses the order and is unable to rectify it until the Days of Tashreeq have ended, a sacrifice (dam) becomes obligatory upon him. This applies to someone who is certain or doubts that the order was not observed before completing the throwing. However, for someone who completed his throwing without doubt, and then doubt arose afterwards, nothing is required of him, because a doubt that arises after an act of worship does not affect it.