Amazon Ads – Active products not showing when creating a new campaign

Is anyone else having this issue with Amazon Ads?

When creating a new campaign, the Products section shows “There are no available products for your campaign.”

But if I go into an existing campaign → Add products, the exact same ASINs are available and can be selected (so do every other ASINs, it appears for me to select)

I’ve also tried:

• Searching the ASIN manually
• Uploading the ASIN
• Using active listings (existed for years and are already running in other campaigns)

So this is not an inactive listing, new listing or internet issue.

It seems like Amazon’s new campaign builder isn’t pulling the available ASINs correctly, even though the products are clearly eligible and already being advertised.

Has anyone else experienced this recently? Any fix or workaround?