If you want to add an ASIN to your account, follow these steps:
Click on your Sponsored Products in the left hand column in your account
2. Click on the Products tab
3. At the bottom of the Products box, click the button that has a plus sign. Hovering over it will say "Add ASINs Manually"
4. In the pop-up box, enter the ASIN(s) you want to add on the left hand side one-by-one and press enter (you can add up to 150 at one time)
5. Click confirm
6. A message box should appear indicating that the ASIN has been added successfully
When you look up the ASIN, you should now be able to find the product!