You need to be using a project referencing .NET Standard (any version of .NET Core or .NET Framework 4.6.2 or above).

PM> Install-Package Nexosis.Api.Client 

The most basic thing you can do with the API is submit some data and ask for predictions all at once. This can be done if you have a CSV file with the following code:

   var client = new NexosisClient("YOUR API KEY HERE");
   using (var file = File.OpenText("C:\\path\\to\\file.csv"))
   {
       var dataSetName = "myfile";
       var data = await client.DataSets.Create(DataSet.From(dataSetname, file));
       var session = await client.Sessions.CreateForecast(Sessions.Forecast(dataSetName, DateTimeOffset.Parse("2017-03-25 -0:00"), DateTimeOffset.Parse("2017-04-25 -0:00"), ResultInterval.Day, "sales"));

       Console.WriteLine($"{session.Id}");
   }

For this to work, the CSV file must have a header with the names of the columns in the file. One of those must be named "timeStamp", and in this example, there is a second column named "sales".

Once the forecasting is complete, you will receive an email notification. Using the sessionId from above, you will want to get results with the following call:

    var results = await client.Sessions.GetResults(sessionId);
    // results has a .Data property with the forecast values

Create a new issue. Please include code to reproduce the error if possible.

Pull requests are welcome.