You don't enter it. Keep it for your records, you may still get a 1099-C for cancellation of debt.
You may get Form 1099-A (Acquisition or Abandonment of Secured Property) if your lender foreclosed on your mortgage or repossessed property as a result of a defaulted loan.
If your 1099-A is for personal property, like your personal residence or automobile, you don't need to report it. However, hang on to this form and keep it with your tax records.
On the other hand, if you got a 1099-A for business or investment property (like a rental), we highly recommend that you consult a tax professional for further advice. If the timeshare was not rented out by you, you do not need to enter this into your return.