Google has started to show errors specifically with the rich results when implemented using RDFa or microdata that incorrectly tag a URL where a text value is expected are now shown as an error in the rich result report. This started on December 3, 2019 and will continue as it goes forward.
Google posted this on the data anomalies page. Google said "The most common case is pages that incorrectly label <a href> tags with itemprop, expecting the text content of the <a> tag to be used, when in fact the href value will be used. A correct implementation in this case would use a nested <span itemprop> tag inside the <a> tag, where the <span> designates the non-URL value."
So when looking at the errors on your reports, please consider this change going forward.
Forum discussion at Google Webmaster Help.