Father transfer property through sale deed in place of gift deed.

A user received a notice under Section 148A claiming they purchased property for ₹15 lakh, when it was actually transferred from their father without payment. They need advice on how to reply to the notice, justifying that a sale deed was mistakenly used instead of a gift deed. The user is also seeking clarification on whether such a transfer via sale deed from father to son is taxable for the father.