Flipkart - Flipkart not returning the defective products and not giving refund for

I had purchased a laptop from Flipkart on **th Jan and product they send was defective and they replaced the product however the replacement product was also defective and since *th Feb Flipkart is giving excuses to not returning the product nor they are refunding the money they are stating that brand technician will visit and check and then only they will refund however it's been * days and no one visited not have any updates on the same . I purchased a new product so why should I wait or go to brand authorised center to return my product.