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I understand that Faxes are initially queued and that I need to periodically poll for the final disposition. What I'm not clear on is how? The following call returns a JSON response:

ResponseBody responseBody = restClient.post("/restapi/v1.0/account/~/extension/~/fax", requestBody);

And in that JSON response there's a "uri" field of the form (edited):

"uri" : "https://platform.devtest.ringcentral.com/restapi/v1.0/account/<ACCOUNT>/extension/<EXTENSION>/message-store/<MESSAGE_ID>"

What I'm not clear on is that exact API call that I need to make and how I make use of the URI. Can anyone supply some sample code? Thanks in advance... :-)