Shiprocket And Ekart Logistics - wrong package returned

I was selling earbuds online. I sent parcel to my first customer via shiprocket. I spent rs. *** just to activate the wallet. then they charged *x the cost of delivery. and after that, the customer whom I sent the product blocked me and returned the parcel. I have the seller's address. after the parcel arrived back. the delivery boy went and I was excited to open the parcel because I was going to use it. But unfortunately, I got a charger in the box. when I tried to raise dispute, there was no submit button on desktop or mobile site. I called their customer care and they said they will investigate and see. and then they don't even reply me. They aren't doing any investigation or anything. I lost my ****rs due to them. They are complete fraudsters. don't use shiprocket