No IP claim, and the first seller does not sell under their brand.
No, you cannot delete the original listing request made by the first seller, even if you were later approved to sell the product. Once a product is in Amazon’s catalog, it remains there, and other sellers can list under it. However, if you created a duplicate listing or variation, you can delete your own offer from your seller account. If there’s an issue with the original listing (such as incorrect details or brand violations), you may be able to request changes through Amazon Seller Support or the Brand Registry if you have brand ownership.