TurboTax interview doesn't support two different types of canceled debt reported on 1099-C. Please consult a professional, or see IRS publications 544 and 4681 before continuing.
You can get IRS forms and publications by calling 1-800-TAX-FORM (1-800-829-3676) or by visiting the IRS website at www.irs.gov.
However, you can add the additional 1009-C using the Forms mode in TurboTax (NOTE: DO NOT OVERRIDE ANYTHING WHILE IN THE FORMS MODE).
To do this, enter the first 1099-c. "Federal Taxes" > "Wages & Income" > "Less Common Income" > Miscellaneous Income" > click start next to "Cancellation of debt (Form 1099-C)..." follow the onscreen guide to enter your first 1099-C form.
Please show me how to enter 2 Forms of 1099Cs in the system.
When you are in the 1099-C section of TurboTax Online, under Wages and Income, and you reach the screen that states "Enter Some Info from Your 1099-C", note that the directions state "If you have more than one 1099-C, add the numbers from each one together and enter the totals below".
See this tax tips article for more information about Form 1099-C.