Ar35FaTSDX7nv2n, TurboTax is behaving correctly.
Using the numbers in your example, the amount reported with code W in box 12 of your W-2 by your employer should have been $3,200, so you should try to get the employer to correct the W-2 to show the entire $3,200 of HSA contributions deposited by the employer on your behalf. If the employer refuses, when asked, tell TurboTax that your employer told you about other contributions made to your HSA for 2020, then enter $2,000 as the amount of these contributions not reported on your W-2. TurboTax will then include the entire $3,200 on Form 8889 line 9.
[Edit] I guess I was a bit too slow in submitting this reply. You should still try to get the employer to correct the W-2 and make the entry that way instead.
