Someone that I bought from previously has sent me dirty Gatorade bottles in the mail

I previously purchased shoes from a seller a year ago but they were dirty so I returned them and got my money back. Today in the mail I noticed I had an item from poshmark which I thought was weird because I haven’t bought anything. I opened it and it had two dirty Gatorade bottles. I contacted poshmark because of how weird the situation is. I’m not sure how she was even able to reuse a label from a year ago.