Punjab National Bank [PNB] — my refund not processed

I have not received my refund which was processed by myntra shopping app on september 13, 2017 under-
Bank reference no.[protected], punjab national bank.
It's has been more than a month and i haven't got any help from bank customer care service. Under name-
Sheetal jangra
Account no. [protected]
Ifsc code - punb0639700.
As reference id was generated so i want to get my refund very soon. It creates a lot of inconvenience for bank customers if these type of issues arise. I have provided my details regarding the situation so please look into the matter.