I'm getting this new error under the Unparsable structured data report for 5 days. I see this report has been newly added and also has some help center article from Google.
Just trying to figure out how to validate and resolve this issue.
After checking Google Help center article, look like the issue is related to JSON-LD being invalid.
The issue seems to be mostly from SEO plugin in WordPress. I use Rank Math SEO plugin on my blog.
WoW! the developer has released an update to the plugin which should eventually fix the error. This is awesome!
You can test any errors to identify the root cause in the Structured Data Testing Tool.