Which validation tool are you using? Google rich results test shows only warnings (not errors) about missing ratings and reviews:
https://search.google.com/test/rich-results/result?id=Rmwa_XpWJK28KzSopduMBQ
Which ratings and reviews plugin are you using?
Which plugin is creating the “_ts_MPN” custom field for your products, and where did you enter the “_ts_MPN” custom field name in the WPSSO settings?
js.
Hello, thank you for your reply! 🙂
I am just looking into the Google Search Console alsmost every day for a quick glimpse. Today the above named warnings appeared newly for more than 2.000 products at once. – So this seems to be a new general error.
Indeed those are all “yellow warnings” (not “red errors”).
I am not using a special rating plugin, except WordPress/Woocommerce itself. And additionally your “WPSSO Add Five Stars”.
The field “_ts_MPN” is created by the Plugin “Germanized”. This plugin offers a field for the MPN int the product editing page.
I entered it at WPSSO > Advanced > Attributes and Meta > MPN Attribute.
And also under Custom Fields > Product MPN Custom Field.
Thank you. (No hurry needed!)
Sandra
FYI, looking at your Schema markup, it looks like the ProductGroup has an MPN (ie. the WooCommerce product), but not the individual products (ie. the WooComerce variations). If your WooCommerce variations do not have an MPN custom field, then WPSSO cannot add that custom field to the markup for variations. If you’re using a plugin to manage that MPN custom field, make sure it allows variations to inherit that custom field as well.
js.
Thank you! I see!
Indeed I am never entering an MPN for the variations, just one for the whole product.
I guess thats not a big thing in the end, if it stays this way now.