Api on .net client

I am implementing .net application to connect xibo api. I added application to my cms, send the consumer key and secret from my app and take the token and token secret without problem. And open the cms with this token to authorize user, after login the cms give an error "

                    There has been an application error.oauth does not support the function: authorizeefddffdddbfaaedaa". and cannot continue. 

Tried to logoff and logon, add another app and different key, nothing helps.
If it possible can you support a little guide to connect api from .net side, maybe I make something wrong.

Hello again,
I found the problem. As xibo Documentation
OAuth methods:

XRDS: services.php?xrds
Request Token: services.php?service=oauth&method=request_token
Authorize Token: index.php?p=oauth&q=authorize
Access Token: services.php?service=oauth&method=access_token

But Authorize Token: index.php?p=oauth&q=authorize should be index.php?p=oauth&q=authorize&oauth_token now I can authorize.

Well - I think that is more of a documentation misunderstanding than an error. The authorize end point is index.php?p=oauth&q=authorize, but you need to append the oauth_token as a GET parameter.

We will make a note to improve the documentation.

Please note the API is still in beta - you may find a few little niggles.