Bayhaqi 21640 — The mukatab remains a slave as long as a single dirham

Sayyiduna Abdullah bin Amr bin al-As (may Allah be pleased with them both) relates: "O Messenger of Allah (peace and blessings be upon him), we hear (hadiths) from you (peace and blessings be upon him); do you (peace and blessings be upon him) permit me to write them down?" He (peace and blessings be upon him) said: "Yes." He says that the first thing the Messenger of Allah (peace and blessings be upon him) wrote to the people of Makkah was this: "Two conditions in one sale are not permissible, a sale and a loan together are not permissible, nor is the sale of what has not come into one's guarantee permissible; and whoever has been given a contract of manumission (mukatabah) for one hundred dirhams and pays all the dirhams except ten dirhams, he is still a slave; or (whoever) has been given a contract for one hundred uqiyahs and pays all of it but one uqiyah remains, he is still a slave."
This is how I found it, and I do not consider it mahfuz (preserved).