There are a few ways to handle this. The one that is best for you is to contact the folks who issued you an advance and request a corrected tax form to show the repayment. They're not likely to want to do it since this is for last year but it never hurts to ask.
The second way is to create a schedule C for a business that shows income in the amount of the advance and an expense in the amount of the return and zeroes itself out.
The third way is to go all the way to the bottom of the wages and income section of TurboTax and click on 'miscellaneous income' and then on 'other reportable income'. Enter the advance you received as "Publishing Advance" and then enter the exact same amount as a negative number and enter "return of publishing advance".
@alm5