Paytm Mall - Used product delivered

I have ordered (id ***********)new product from Paytm mall on ** March and the product I received was used and old one. It already had screenguard(which usually isn't included on new phone).Apart from this , there was no IMEI no sticker on it's back vand have a lot of scratches including it's camera surface. The inner condition within the packaging phone box , a few accessories are missing such as a sim insert pin and the company's logo sticker on front display to safe screen.The package box is also old one as it has a lot of marks over it.The packaging box's sticker outside isn't fixed properly . I have checked online imei no of device it already stated that the product was purchased/activation on **-**-****. So it's your responsibility to provide replacement or refund my money as I have paid it to Paytm Mall. I have raised an inquiry on your website but haven't got any response yet. Even your customer care phone isn't connecting . I' m really disappointed with your service. I want an instant action in this.I want you to refund or replace my product as soon as possible.