´It was narrated from that Safinah - Abu 'Abdur-Rahman-said :` “Umm Salamah freed me but stipulated that I should serve the Prophet (ﷺ) as long he lived.”
Hadith ReferenceSunan Ibn Majah / The Chapters on Manumission (of Slaves) / Hadith: 2526
Hadith Gradingالألبانی:حسن | زبیر علی زئی:إسناده حسن