Product page, variants and WordPress SEO output
Check paginated product archives with different articles. A global SEO template must not combine these following pages unchecked to the first page.
Compare the main variable product with called variant and category paths. The SEO plugin can set the preferred URL, while a customized product template also inserts its own canonical.
Where to check the setting in WooCommerce
Compare the normal product URL to a variant or category path URL. Check the canonical rule of the active WordPress SEO plugin and own additions in the theme. A variant selection alone does not justify a separate indexable product page.
Example of this specific finding
Illustrative control case: /Category/? page=2 shows other products as page one, but refers to /category/ via canonical. The content is not identical.
follow-up audit in WooCommerce
Open a specific variant selection directly and compare it with the main product. The desired URL must match the visible product, price and selection status.
Treat each independent following page with a suitable canonical URL and keep it accessible via retrievable links. Check product distribution and link path.
Derogations and scope
A true full view-all page requires a separate decision. Not every page-two URL has to get the same rule without looking at the content.
Regarding: WooCommerce on WordPress. Block and classic product templates as well as SEO extensions can have different output locations.
Classify the general error
Definition, system-independent causes and further correction examples: Subsequent pages are not automatically duplicates of page one