Sunan Ibn Majah
2520
Daif+3

It was narrated from Umm Salamah that the Prophet (ﷺ) said:“If anyone of you (women) has a Mukatab, and he has enough (wealth) to pay off (his contact of manumission), she must veil herself from him.”

DaifAl-Albani
DaifMuhammad Fouad Abd al-Baqi