It appears that TurboTax 2021 for Mac is ignoring Total Medical Deductions (Schedule A, line 14), inserting a zero into Itemized Deductions, Medical & Dental on the Two-Year Comparison and defaulting to Standard Deduction on Line 12a of Form 1040. In my case, my Itemized Deductions exceed the Standard Deduction by several thousands of dollars, but TurboTax appears to be defaulting to the Standard Deduction while ignoring Schedule A, Line 14.
Schedule A, line 14 reports the total of your gifts to charity, so I think you may be referring to line 4, which is your deductible medical expenses.
If so, you need to keep in mind that you can only deduct the amount of your medical expenses that are more than 7.5% of your adjusted gross income. So if your allowed medical expenses are not more than 7.5% of your income, as is typical, you will not have a deduction for medical expenses appearing on line 4 of schedule A. That may be why your standard deduction is more than your itemized deductions.