If you want to remove a catalogue item from your product list, you can do it in several ways:

By clicking on the "Product Catalogue" menu item in Marketplace: in the Product Catalogue, click on "My Sales" from the filters, then tick the "Only what I sell" option. In the products that appear, click "Remove from my products" on the product cards, then click Sync - this will remove the product from your Product List.

You can also remove products from your Product List individually or in bulk.

For detailed instructions on how to delete products, please see the following page:
​Delete Products