last price mam

Ma'am a miss was selling new heels at 450 but I wanted used heels so I requested her to wear those heels. Since she was a student so she agreed to use the heels when she go to college but for that she charged 1200 and told to pay immediately in upi so I paid. And now she is telling again pay 1000, so I am not getting trust. So should I purchase from you or her.