Thanks for the swift response.
I did install WPSSO SSM on 17th November, and re-upped my site map. The errors are dating at 18th November now, so it doesn’t seem to have fixed it.
I have just installed https://www.ads-software.com/plugins/wpsso-schema-json-ld/, in preparation to the template modification you suggested. I will re-upp the site map and check in next week. If the errors are still there I will modify the template as you suggested.
Thanks again for the response.
