Do we have to pay home sale tax? We had home office and took depreciation. Calculated the adjusted basis. Final profit $300K. TT is not giving us the 500K exclusion.

The adjusted basis was calculated by purchase price + improvements - depreciation from home office. Profit was Selling price - Adjusted basis which was $381K.  Turbo tax states no income tax on $325K but have to pay tax on $55K which is the amount of the depreciation over the years.  We are filling joint return and I thought we had a $500K exclusion. Can someone explain?  Thanks in advance.