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No subfolder is specified in the MQTT topic
A subfolder is specified in the MQTT topic , but it doesn't have a matching device registry’s Pub/Sub topic in the device registry
For example, if the device publishes to the MQTT topic /devices/DEVICE_ID/events/alerts, the subfolder is the string alerts. Messages are forwarded to the additional Cloud Pub/Sub topic if the eventNotificationConfigs[i].subfolderMatches and eventNotificationConfigs[i].pubsubTopicName fields are set to alerts. Otherwise, messages are forwarded to the default Cloud Pub/Sub topic.
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