IRS Notice CP28

Got a notice that there was an error on my 2024 return for the Home Mortgage Interest Deduction calculation.  I did go into the Amend return to see if I entered the correct amount that was on my Mortgage statement and I did.

My mortgage is over $750k so I am not entitled to the full deduction but I can't see how Turbo Tax calculated the amount it used (which was less than the full amount that I entered in so Turbo Tax did reduce it).

 

I can't get anyone on the phone to help me figure out if the calculation was right or not - any idea how I can get someone on the phone to help me with this 2024 calculation?