Myntra.com — I'm complaining about refund which Myntra not returning

I had ordered a dress (women pink embroidered A line dress of DressBerry brand). I received dress on 8th September 2021 when I tried dress due to bad fitting i decided to return it. I requested for the return within 30 min on the same day and return picked up on the same day. After the message was sent on my mobile that the pickup was successfully completed i got another message saying my return request was "put on-hold" as it "failed to pass the quality check". When I called to customer care and explain them that I had returned product as it is with tags n all.they said I will get refund in 3-4 days but it's been more than 5 days no refund processed. they haven't changed product status even marked it as "return rejected". So now they have pruduct with them and also amount not refunded.not allowing me log ticket on their site even so its clearly seems they are doing fraud as they have taken pruduct from me now my amount also not refunding.please help.