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Go to Visualization
Click on Create new Visualization
Add a bucket and select the X-axis.
Select the following
Aggregation - Terms
field - express.voiceAnalytics.voiceAgent.attributes.mycontextData.series_name
Click on the play button.
You will find the visualization of data on the right.
Save the visualization if you like it or fiddle with the many options here to get the required visualization.
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