1. Check that the device's device group is selected in the visualizer integration
    1. In the WebUI, open the Integration's page
    2. Scroll down to the section Device Group Selection
    3. Select the device group containing the device of interest 
  2. Check that the core is connected to InfluxDB
    1. In the WebUI, open the Integration's page
    2. In the section Connection, look for the setting Measurement Name
    3. The field contains either the measurement name (a string beginning with visualizer__) or an error message
    4. If the error message is Not available, check data source, then restart the core to reestablish the connection to InfluxDB