A website is selling counterfeits with my trade mark

You have several remedies. As the owner of a registered trade mark, you can bring proceedings under the Trade Marks Act 2002 for infringement and seek injunctions, damages or an account of profits, and there are criminal offences for knowingly dealing in counterfeit goods. You can report the listings to the online platform or host, using their intellectual property complaint process, which often leads to swift removal. You can notify New Zealand Customs Service to request border protection so that infringing goods can be detained on import. Preserve evidence, including screenshots, test purchases and details of the seller. Send a cease and desist letter if the seller is identifiable, and consider legal advice for cross-border actions, since enforcement against overseas sellers can be difficult.