Let's set up the "Audience". Go to "Configure" => "Audiences" section. And click "new audience".

Then click "Create a custom audience".

Enter a name for the new audience (for example, "Missed_calls"). After that, set up the conditions:

Click "Events" and select Ringostat_calls.

Add the "call_status" parameter.

For conditions, select "matches regex" and set the value: "(CLIENT NO ANSWER|NO-FORWARD|NO ANSWER|BUSY|FAILED|VOICEMAIL|NO EXTENSION)".

Don't forget to specify "Audience Trigger" without spaces. For example, "Missed_calls".

Save the audience.

The last step is to set up conversion for this audience. Go to the "Configure" => "Conversions". And click "New conversion event".

Give the conversion name the same as the audience trigger — "Missed_Calls" and save.

Conversion events are automatically enabled.