Image copyright infrintement on ecommerce platforms

I have two questions to ask: Q No. 1). I am an online seller on amazon and Flipkart eCommerce platforms. As per amazon's selling policies, if someone has listed a product, no other seller is allowed to copy the bullet points, product titles, and product image. A few days ago some sellers copied a few parts of product bullet points and a few parts of product titles from originally created listings of mine. I complained to Amazon about the same and amazon's software deleted the offender's listings from the website. The offender now contacted the amazon seller support team and reactivated the listings. Now the offender has sent me an email and has been asking for Rs 10000 compensation for the listings deletion and impact on his business ( for not getting sales on those listing for one whole day) because as per him no part of the listings was copied from my listings. He has given me 2 days of ultimatum, otherwise, he will file a lawsuit against me for wrongly claiming copyright infringement. What should I do now? I didn't delete his listings. It's amazon's software that deleted his listings upon being informed by me. Is he legally right to file a lawsuit against me? Q. No. 2). The same seller has been using a few of my product images (solely clicked and edited by me for eCommerce product listing purposes) on various eCommerce platforms as well as two websites owned by him. He downloaded those images from my listings on amazon and since then has been using the same on the eCommerce platforms (against my listings) and two of his websites. I have all the raw images with me as well as the images that were auto uploaded on google photos (with non-editable location details, device models, etc) at the time they were clicked by me with my own mobile phone. Recently, I asked the seller to remove those images and compensate me for the loss I have been suffering due to him using my images against my listings without my permission, he didn't remove the images by saying the court will not entertain my case as my images are not registered with the copyright office. Can I sue him for illegally using my product images without my permission? Will the lawsuit enforced in court even when I have not registered my images with the copyright office? Please guide.