Edited Issue: Tweet favourite [2096]

I am trying to mark a tweet as a favourite, I have the authorization token and am able to view profile details. When I search for tweets I get back list but I am unable to mark any as a favourite, I receive and exception and a message "Value cannot be null. Parameter name: s"

System.ArgumentNullException was unhandled by user code
HResult=-2147467261
Message=Value cannot be null.
Parameter name: s
Source=mscorlib
ParamName=s
StackTrace:
at System.IO.StringReader..ctor(String s)
at Newtonsoft.Json.Linq.JObject.Parse(String json)
at TweetinviLogic.Wrapper.JObjectStaticWrapper.GetJobjectFromJson(String json)
at TweetinviCredentials.TwitterAccessor.ExecutePOSTQuery(String query)
at TweetinviCredentials.TwitterAccessor.TryExecutePOSTQuery(String query, JsonConverter[] converters)
at TweetinviControllers.Tweet.TweetQueryExecutor.FavouriteTweet(ITweetDTO tweet)
at TweetinviControllers.Tweet.TweetController.FavoriteTweet(ITweetDTO tweetDTO)
at TweetinviLogic.Tweet.Favourite()
at TwitterBot.UnitTest1.search() in c:\Users\andrew\Documents\Visual Studio 2013\Projects\TwitterBot\TwitterBot\UnitTest1.cs:line 89
InnerException:

__Update__:
It appears that only some tweet throw the exception over half.
Comments: ** Comment from web user: linvi **

Hi there,

What is the issue that still exist?
Is it the fact that the application crashes or the fact that the Favourite flag is invalid?

If it is the latter, it probably means that Twitter does not send you the valid operation. I remember having testing this feature before publishing it.

If the issue is about the favourite property being invalid, I think I will need you to share your credentials with me as well as the code that sends you invalid data. It will allow me to confirm the problem.
Could we discuss about this on private (contact page)?

Regards,
Linvi