What is the ruling on delaying Asr prayer until Maghrib due to being busy with calculations, and is this prayer accepted?

A person's preoccupation with calculations is not a legitimate Sharia excuse for delaying the Asr prayer past its time. He must promptly seek forgiveness for falling into a grave sin and be keen not to return to it. If the prayer is performed with its conditions and pillars, along with sincerity, then it is accepted, Allah willing, based on His (the Almighty's) saying: "Indeed, Allah only accepts from the righteous [who fear Him]," and what is meant by "righteousness" (taqwa) here is the avoidance of polytheism, and the devotion of the righteous of this nation is prayer.