Docusign activity has a problem (TokenResponseException)

Hello,
i am trying to use the UiPath Docusign Activities. When I use the docusign application scope with OAuth2AuthorizationCode it opens the browser and there is the message: “Received verification code. You may now close this window.”.
Also the Redirect URL must be correct.
After this I get the following exception:
“Server response does not contain a JSON object. Status code is: Forbidden”

Does anyone know what this means? It looks like studio can´t receive the token from the browser. It is a TokenResponseException