What is the ruling on someone who was preoccupied and missed the Dhuhr prayer at its time without realizing it, and when the muezzin called for the Asr prayer, he attended the prayer in the mosque thinking he was praying Dhuhr, having intended to perform the Dhuhr prayer? When the sun set, he realized the mistake he had made and prayed Maghrib, then he stood up to make up the Dhuhr prayer even though he had already prayed it during Asr behind the imam. What should he do? Is the prayer he performed behind the imam during Asr considered as Dhuhr with the intention of Dhuhr? Does he need to repeat the Dhuhr, Asr, or both?