I doubt that there is any problem with TurboTax. It works fine for me for various combinations of contributions and HDHP coverage.
I think you are indicating that line B of the Line 3 Smart worksheet shows $3,225 but line 3 shows $3,225 instead of $3,975. Just to be sure, check that your age as of 1-1-2026 shown on your Personal Information Worksheet is at least 55.
