Clicking on global tag yields "Nothing found for search term(s)."

I've done a related post here, but I believe I've seen this behavior before with Global Site Tags. The tags seem to be indexed correctly, and the tags page displays fine, but clicking on any tag yields "Nothing found for search term(s)" instead of the posts. Have others observed this behavior? I've re-run Post Indexer, re-saved permalinks settings, even flushed the back-end cache.

Thanks,

Jim P.