Amazon Pay - Refund realated issues

I ordered an Tribit x free go over ear bluetooth headphone on ** july **** after delivery of the product i open it an tried to use it but it did not work and i return the product for refund and a delhivery agent picked it up on ** Aug **** after * days of pickup i called them that the item has been picked up from me but not showing on your system they told me that there are some problems it will be start showing pickup in ** to ** hours after that i called them again they told me that wait for * to * days you will get your refund after * days i called them again and they told me again to wait every time i called them they said to me to wait i had called them more than ** times but every time they told me to wait and i called them again today they said to me again to wait * to * days they are wasting my time from * months please help me to get my refund amount.