"The contractual obligation regarding a slave lasts for three days." (1)
Sunan Ibn Majah Book 12, Hadith 108
← Previous Hadith a man bought a slave and put him to work, then he found some defect in him, so he returned him. He (the seller) said: "O Messenger of Allah he put my slave to work." The Messenger of Allah (ﷺ) said: "A slave's earnings belong to his guarantor."

Sunan Ibn Majah Book 12, Hadith 107 Next Hadith → "There is no contractual obligation after four (days)."

Sunan Ibn Majah Book 12, Hadith 109