Hi Raphael,
I think this is a good question to post on the developer forum.
If the customer number is wrong and the call cannot be completed you can have a look at the conversation details and check what you are getting back from the telecom (SIP 404, 480, 503...).
Another thing you can try use and determine who hang up first is the disconnectionType.
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Paulo Mesquita
Spark NZ Trading
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