TTK Prestige — Refund o[censored]ndelivered item

I ordered an item through their website .un fortunately the item didn't get deliver .when I called after 13 days of delay the customer care representative told me that the item is returned as the courier partner couldn't find my address in hyderabad city neither they called me also.
Now the amount refunded was 620 rs to my account which I paid through bank and the remaining voucher amount of Rs 2000 was not credited back.Its been 80 days, 70 calls, 30 emails still they are making fool of me saying the issue will be resolved soon.
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