To add Negative ASINs for Automatic campaigns, please take the following steps:
1. In the Optimize section, go to Campaigns tab and click on the Automatic campaign(s) that you want to add Negative ASINs to. Note that these campaigns contain "AUTO" in the title (vs. MANU for Manual campaigns).
2. In the Ad Groups tab, click on the associated ad group.
3. You can then add Negative Keywords and/or Products by typing in the box and choose type (Keyword or Product) and match type (Negative Exact or Negative Phrase) from the drop-downs.
Please note we are unable to add products at a campaign level.