Kathy (ohkathy) mercari Ohkathy - Thief / Conwoman/ Online Predator Islip terrace Ny

posted items to sell online using mercari and on 9/3/2023 I received an offer to purchase my new therabody Roller massager and had pics , description etc as all was new and never used and only opened to see all worked perfectly before shipping and when wrapping back I used a rubber band to secure plug put all back in packaging exactly as I received and sold for half of what I paid immediately shipped out and all the while posting status and that I hope you enjoy etc as I have sold many items and Never had issue but this time 10 mins after confirming she received she posted that she wasn't paying because charger was wrapped with rubber band again this is what she bought off mercari an online spurce for people to sell to one another and much less then original cost and this woman actually stole and never paid nor received back and she hides behind nothing more then user name OHKATHY ON mercari and mercari doesn't help as they do not have customer service number nothing to reach to them and immediately accept her request and now I'm here without my item nor money empty handed I'm so upset and feel at a loss and only doing sales to supplement money for my family it's not much but lot to me and feel so violated and frustrated that someone who works the system takes advantage out of regular people just trying to supplement income and would appreciate any and all help thank you - please be careful when buying online as these people work these systems and that people like myself so naive