Does the problem lie with C4 sending out the MQTT commands, or with BI acting properly on incoming MQTT commands?
I don't use C4 for my automation system and I don't change BI profiles using MQTT, so I'm not exactly an expert on the topic. But that would be the first thing I would figure out to understand where the problem arises. You can use an MQTT client to conduct these tests and monitor the MQTT traffic to see which end the problem lies.