Flipkart — Product replacement not done and Rs 50/- deducted as return fees

I am suman kalyan maiti. My registered mob no in flipkart is [protected]. Product order id is od[protected]. I have ordered for a replacement o[censored]s polo round next blue t shirt of rs 560/-as they have delivered me an used product without any brand tag. But they have neither picked my used product not delivered the replacement product. I have talked with the flipkart executives several times. But they said replacement is not possible, only return is possible. So i have returned the product. After pick up, i have seen that rs 50/- was deducted as return fees from my refund amount. How can they deduct this price?? It is entirely their fault. They have not delivered the used product. After that they have not delivered the replacement. Also they adviced me to return the product as replacement is not possible. Then how can they deduct return fees??
They have wasted my valuable time, also money. I need compensation for this with this deducted fund. This type of fraud should not be tolerated.