"I made a vow during the Ignorance period and I asked the Prophet (ﷺ) (about it) after I became Muslim. He told me to fulfill my vow."
Sunan Ibn Majah Book 11, Hadith 40
← Previous Hadith "Whoever makes a vow and does not state it specifically, the expiation (for such a vow) is the expiation for breaking an oath. Whoever makes a vow and is not able to fulfill it, the expiation for that is the expiation for breaking an oath. Whoever makes a vow and is able to fulfill it, let him do so."

Sunan Ibn Majah Book 11, Hadith 39 Next Hadith → "O Messenger of Allah, I vowed to offer a sacrifice at Buwanah." He said: "Do you intend any action of Ignorance period?" He said: "No." He said: "Then fulfill your vow."

Sunan Ibn Majah Book 11, Hadith 41