James Kirsop - There is no direct way to identify if a user declined a call from the call record data. The call record data provides usage and diagnostic information about the calls and online meetings that occur within your organization when using Microsoft Teams or Skype for Business. It does not provide specific user actions such as whether a user declined or answered a call.
To achieve your requirements, we recommend you give your feedback in Teams Feedback Portal.
Thanks,
Prasad Das
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