The Messenger of Allah ﷺ said, "Whoever prays the dawn prayer is under the protection of Allah, so do not violate Allah's protection , lest He hold you accountable for anything regarding His protection."
حدثنا أسود بن عامر حدثنا حماد بن سلمة عن علي بن زيد وحميد عن الحسن
أن رسول الله ﷺ قال من صلى صلاة الفجر فهو في ذمة الله فلا تخفروا ذمة الله عز وجل ولا يطلبنكم بشيء من ذمته
Its isnad is sahih, via the route of Humayd, hasan via the route of Ali. Muslim narrated the hadith, 1/454, no. 657, in Masajid, on the virtue of the Isha and Fajr prayers. And Tirmidhi, 1/434, no. 222, in Prayer, on the virtue of Isha and Fajr, and he said, hasan sahih.