rude manager and poor customer service - Consumer Complaint for PEP STORES

i went to pep cell at midrand boulders shop no 4365, bought earphones around 10, found out they were not working, went back to the store around 11, and they told me they cant exchange them, i asked for refund and they still refused. i called headoffice and they not picking up. what must i do with earphones that are not working????????