Myntra.com — Refund refused due to item number mismatch

I received my shirt and initiated return within one hour due to wrong fit. I only tried it once and left the tags intact. But my refund was refused due to item number mismatch. I talked to customer care twice but they haven't provided any additional details. I asked for call back from supervisor but received no further call. I came to know this happened to a couple of people I know and they were refused inspite of giving all the proofs.