The Verse of Hajj-at-Tamatu was revealed in Allah's Book, so we performed it with Allah's Messenger (ﷺ), and nothing was revealed in Qur'an to make it illegal, nor did the Prophet (ﷺ) prohibit it till he died. But the man (who regarded it illegal) just expressed what his own mind suggested.
Sahih al-Bukhari Book 65, Hadith 43
← Previous Hadith I sat with Ka`b bin Ujra in this mosque, i.e. Kufa Mosque, and asked him about the meaning of: "Pay a ransom (i.e. Fidya) of either fasting or . . . . (2.196)" He said, "I was taken to the Prophet (ﷺ) while lice were falling on my face. The Prophet (ﷺ) said, 'I did not think that your trouble reached to such an extent. Can you afford to slaughter a sheep (as a ransom for shaving your head)?' I said, 'No.' He said, 'Then fast for three days, or feed six poor persons by giving half a Sa of food for each and shave your head.' So the above Verse was revealed especially for me and generally for all of you."

Sahih al-Bukhari Book 65, Hadith 42 Next Hadith → `Ukaz, Mijanna and Dhul-Majaz were markets during the Pre-islamic Period. They (i.e. Muslims) considered it a sin to trade there during the Hajj time (i.e. season), so this Verse was revealed:-- "There is no harm for you if you seek of the Bounty of your Lord during the Hajj season." (2.198)

Sahih al-Bukhari Book 65, Hadith 44