Poshmark 1099

This year I began selling on Poshmark.  Based on my sales report I will be receiving a 1099 from Poshmark because I have hit the $600 mark.  All items I have sold have come directly from my close and not sold for profit . For example, if a shirt was originally $50, but it sold for $20. I know I am required to include the 1099 In my tax return, but will I be taxed on that money since the items were sold for less than I bought them for? And when I am filling out my taxes on turbotax, where do I include the 1099 and say these items were sold at a loss?