Myntra.com — refund successfully processed but not received

I ordered a Roadster sweatshirt order no.[[protected]-5753903] for rs 584 and I received it on 3rd December but it it didn't fit me so I made a return request and I an executive pickup the same and Myntra processed the refund on 6th December and it's 12th December and I still didn't receive my refund they also provide me a bank reference no but I didn't get any information from the bank so I have a humble request you to pay attention to my complaint
Thank you