The Prophet ﷺ said, "Whoever sleeps through his witr prayer should pray it when he wakes up in the morning."
حدثنا قتيبة
أن النبي ﷺ قال من نام عن وتره فليصل إذا أصبح
No references are available.
Sourcing, [sahih] see the previous hadith. The statement of Ahmad about Abdullah bin Zayd bin Aslam is sahih and confirmed from him, and likewise the statement of Ali bin Madini.