Did you get a paper IRS notice in the regular postal mail, or did you get an email or text? If it's an email or text, it's a scam. Ignore it, and you can ignore the rest of this reply. The IRS does not send notices by email or text.
If it's a paper notice, what is the notice number or letter number at the top right, starting with CP or LTR? Read the entire notice carefully. Does it say how much your deduction was, and how much they think it should be? Is the amount that they say you claimed the same as the amount on line 8a of the Schedule A in the 2024 tax return that you filed?
There are basically two possibilities. Either the amount that you entered in your tax return is more than the amount in box 1 of the Form 1098 that you received from the lender, or your deduction exceeded a limit. The itemized deduction for home mortgage interest is limited based on the outstanding balance of the loan, not on the amount of the deduction. Check that the amount that you entered in boxes 1 and 2 of the 1098 in TurboTax is the same as the amounts in boxes 1 and 2 of the actual 1098 from the lender.
