My goods not returned to me

Hello I was in need of some money and put my phone up for buy back ... Another customer did the same at Cash Crusaders. When I returned and paid to get my phone back they advised me that someone at the store made a mistake and took out my phone and sold it ... The other customer didn't't come to fetch his phone and they where suppose to sell his phone but the sold mine in stead. it has been 5 days and i still didnt get my phone as the manager told me she would fetch it on the day i paid for it .... my mother went to fetch it at a time she gave and she still didnt get the phone she told my mother she will come drop it herself at my house ..... Everyday since then I called her and she told me I'm dropping it later always close to the time the shop closes and she never seems to come. What do I do if the phone is not in the condition I left it in ? she phoned the guy to let him know what happened and she is fetching the phone ... what if he damage my phone what should I do ? please help.