Truecomretail — samsung a50

I have placed my order on flipkart on 17th for samsung galaxy a50 phone. I have cancelled the order the next day and the refund message has came to me. But still i haven't received any refund amount in my bank. Bank staff are saying that seller haven't processed refund to us. What should i do now? We cannot trust prepaid orders for this purpose. Now i need money for another booking and it's taking long