TurboTax has retained incorrect information about my car. It was leased. It was repossessed in September. TT is treating it like it was owned and sold.

TurboTax retained the information that you entered.  There is a question in the Vehicle Expenses category that asks whether or not you own or lease the vehicle as there are different rules for each scenario.   You may need to amend your previous tax return if you took deductions (depreciation) that you were not qualified to take, but that depends on what you on filed your 2018 tax return.  

You can use either the standard mileage or actual expenses method for a leased vehicle. However, if you use the standard mileage rate, you cannot switch to the actual expense method in a later year.

• • If you use the standard mileage rate for a leased vehicle, the lease payment amount is not deductible.
  • If you use the actual expenses method, leased vehicles are not depreciated.  Instead, the business portion of the lease payment is deducted.