The last words of the Prophet ﷺ were, "The prayer, and those whom your right hands possess."
حدثنا سهل بن أبي سهل حدثنا محمد بن فضيل عن مغيرة عن أم موسى
كان آخر كلام النبي ﷺ الصلاة وما ملكت أيمانكم
[Its chain of transmission is daif]. Abu Dawud narrated it in the Book of Manners, chapter on the rights of the slave, hadith no. 5156, from Musa, whose reliability is unknown. The hadith also has a version narrated by Muhammad bin Fudayl through the same route. Mughira transmitted it using the "an" form, as mentioned previously at hadith no. 1302. As for the corroborating narrations, they are all daif.