Missing metric value on MSK Prometheus

We have a MSK cluster with prometheus monitoring enabled. We are monitoring the consumer lag on different topics on a grafana dashboard. The metrics are collected by a prometheus docker every minute and sent to our prometheus workspace. I've noticed that the exporter does not seem to give us the value of the lag everytime we call it. As you can see in this screenshot, some values of the consumer lag seem to be missing. This is a problem since the consumer lag is a critical metric which we need to be aware of anytime. We are using the metric kafka_consumer_group_ConsumerLagMetrics_Value to get this value. Even by doing a curl on the MSK exporter url, the call sometimes returns a value and sometime does not (when grep on a specific GroupId that we want to monitor).