Tipo de error: "Too Many Requests". Mensaje de error: "Quota exceeded for quota metric 'Search Queries' and limit 'Search Queries per day' of service 'youtube.googleapis.com' for consumer 'project_number:392446688885'." Dominio: "global". Razón: "rateLimitExceeded".

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

Comprueba en YouTube si el id UCxYK-f0OeNyG1mpVPpD0d1Q corresponde a un channelid. Revise el FAQ del plugin or envíe los mensajes de error a support.