The Messenger of Allah ﷺ was once preoccupied from it (meaning the night prayer) one evening, delaying it until we had fallen asleep in the mosque, then woken, then fallen asleep again, then woken once more. Then the Prophet ﷺ came out to us and said, "No one among the people of the earth is waiting for this prayer except you."
أن رسول الله ﷺ شغل عنها (أي صلاة العشاء) ليلة، فأخرها حتى رقدنا في المسجد، ثم استيقظنا، ثم رقدنا، ثم استيقظنا، ثم خرج علينا النبي ﷺ، ثم قال: ليس أحد من أهل الأرض ينتظر الصلاة غيركم.
Bukhari narrated it in the Book of Prayer Times (570), and Muslim in the Book of Mosques (639), both from the hadith of Abdul-Razzaq, who said, Ibn Jurayj informed me, who said, Nafi informed me, who said, Abdullah bin Umar narrated to us, and he mentioned the hadith. The full hadith will come later in the Book of Prayer.His statement, "until we slept lying down," does not mean lying flat, as might first come to mind, but rather it means we slept sitting down, that is, we slept while seated, and sleeping while seated does not invalidate wudu, as is apparent from this hadith.