In DocuSign Envelopes can have status as well as Recipients. For instance, let's say you have an envelope with 2 sequential recipients, the first recipient has signed, and the envelope has been sent to the second recipient. In this scenario, the overall envelope status would be Processing, the first recipient status would be Completed, and the second recipient status would be Delivered (if they have viewed the envelope or Sent if they have not viewed it yet.
See "Recipient Statuses" section on this page from Dev Center
So instead of getting the Envelope status you need to make the API call to get Recipient status. Details of that call are:
GET /accounts/{accountId}/envelopes/{envelopeId}/recipients
Optional query strings: include_tabs={true or false}, include_extended={true or false}
Sample Response:
{
"agents":[]
"carbonCopies":[],
"certifiedDeliveries":[],
"currentRoutingOrder":"String content",
"editors":[],
"inPersonSigners":[],
"intermediaries":[],
"recipientCount":"String content",
"signers":[{
"deliveredDateTime": "String content",
"recipientAuthenticationStatus":{
"(authentication status result)":
"eventTimestamp":"String content"
"status":"String content"
}
},
"recipientId": "String content",
"requireIdLookup": "String content",
"roleName":"String content",
"routingOrder": "String content",
"signedDateTime": "String content",
"status": "String content",
"email": "String content",
"name": "String content" }]
}]
}
See page 191 of DocuSign API Guide for more info