You set a canonical for this page, but Google chose a different address as the original. Google overrides your choice.
Google then shows the other address in the search results and gives it the value. That is often a sign of duplicate content or mixed signals.
With Search Console connected, Snaglist compares the canonical Google chose with the canonical the page has now, for pages that answer with 200. Differences are listed with both addresses.
Snaglist runs this check and 43 others on every page of your site, every week. 14 days free, no credit card needed.
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