Alex here, from the Shopify support team.
Did you use the last column on your CSV to add your products to a collection?
This error would arise when there's a "Collection" column in the CSV, and the collection that you've dictated for the product is an automatic collection, not a manual collection. If the product doesn't fit the conditions of the automatic collection, it would result in this error. Here's a snippet from our help documentation on the "Collection" column in CSV files (link below):
Enter the name of the collection you want to add this product to. If it is an existing automatic collection, then the product needs to meet the conditions for the collection. If the collection does not already exist, then one will be created for you.
I would also recommend looking over your CSV file and making sure it follows the same formatting as you can see in the example CSV or column description section here.
I hope this helps, but if you're still running into errors, feel free to let me know here or reach out to our support team directly via phone, email or live chat - they can definitely help with CSV errors!
Alex | Support