title: How to work with refresh token in DocuSign
body: <p>I am using docusign authentication flow as</p>
  <p>On Sign In<br />
  let url = &quot;https://account-d.docusign.com/oauth/auth?response_type=token&amp;scope=signature extended&amp;client_id=39b5f6fb-97ca-XXXXXXXXXXXXX&amp;state=a39fh23hnf23XXXXX&amp;redirect_uri=http://localhost:4200/callbackdocusign&quot;;</p>
  <p>window.open(url, '_self');
  after successfully validating it return access_token/expires_in/token_type/state.</p>
  <p>please guide how to get refresh_token?
  after refresh_token how to obtain new access_token?</p>
  <p>For refresh_token I tried as
  let url = &quot;https://account-d.docusign.com/oauth/auth?response_type=refresh_token&amp;scope=signature extended&amp;client_id=39b5f6fb-97ca-XXXXXXXXXXXXX&amp;state=a39fh23hnf23XXXXX&amp;redirect_uri=http://localhost:4200/callbackdocusign&quot;;
  window.open(url, '_self');</p>
  <p>But it is not returning refresh_token</p>