PharmEasy — Not refunding money

My mother have ordered medicine in pharmeasy and doctor told to discontinue the medicine.so she kept return for the one medicine and due to lack of knowledge and by default it is selected one and she gave 3 sheets of medicine to courier guy.And when got refund for only one sheet, I have called and raised a complaint and they said that they will refund for 3 sheets when they got confirmation that they received 3sheets and now they are telling that they won't refund and will not send the medicine back.worst service by pharmeasy.