Form 1099-C is available with TurboTax Deluxe. It's hard to tell what the issue is without knowing more about your return.
As a way to diagnose the problem, first is the correct method to amend a return followed by entering 1099-C.
If you have additional questions or details regarding this, please feel free to post in the comments for further clarification.
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https://ttlc.intuit.com/replies/5107826
