Ash-Shaykh Ahmad an-Najmi, rahimahullah, was asked:

The Questioner: “A woman says she was in an exam at school and she was late for the prayer since the duration of the exam is in one period between two prayers [i.e. Dhuhr and Asr]. So she was late for the prayer to the point the time for the second prayer came in. So what is upon her to do?” The Shaykh: “The time for the second prayer came in while she hadn’t prayed yet?” The Questioner: “Yes, she was still at school in the exam. For example, she was in the exam between the time of dhur and asr, the time for Dhuhr ended and the time for Asr came in, [all of this] while she was still in the exam at school.” The Shaykh: “This is not permissible. It is not permissible.” The Questioner: “Also another thing to add oh Shaykh is that especially in the winter season, the time between Dhuhr and Asr is probably only an hour or an hour and a half.” The Shaykh: “Yeah, possibly.” The Questioner: “Especially during the winter season.” The Shaykh: “We say if she knows that the time [between the two prayers] is short, then she should fear Allah and preserve the prayer in order that she doesn’t miss it. So she became lenient to the point the time for the prayer had ended, so she…[word unclear in the audio], if the person did it intentionally. Therefore she should seek forgiveness from Allah and repent to Him and she should make up for this prayer and she shouldn’t do the likes of this action ever again. She should pray salaat in its prescribed time.” 📜 Source: https://torontodawah.com/the-ruling-on-the-prayer-time-ending-while-one-is-writing-an-exam-shaykh-ahmed-al-najmee/