Excess Contriution to HSA

Situation:

--Individual employed in two positions, both of which have employer-sponsored health plans (reflected in code, DD, in box 12a on W-2.  One of the employers also makes a contribution to an HSA.  The entire of this contribution ($1640) is being characterized as excess by TurboTax.  This is the only HSA for this individual and well under the $3550 cap for contributions to an HSA.

Question:

-- Why is TurboTax treating the entire and only contribution as excess?