Error type: "Forbidden". Error message: "Requests from referer https://www.googleapis.com/youtube/v3/search?part=snippet&channelId=&maxResults=9&order=date&type=video&key=AIzaSyB8uhslerKOIx3fHnKHg4E8V54Ag6MviZg are blocked." Domain: "global". Reason: "forbidden".

Did you added your own Google API key? Look at the help.

Check in YouTube if the id UCbBZeeEOTb1f5vEFnv7CU4Q belongs to a channelid. Check the FAQ of the plugin or send error messages to support.