246 Error for RestClient C#

Trying out this API for the first time and wanted to check out an example code.
But it gives an Error for RestClient

class MeanReversionPaperOnly
private string API_KEY = “REPLACEME”;
private string API_SECRET = “REPLACEME”;
private string API_URL = “https://paper-api.alpaca.markets”;

    private string symbol = "SPY";
    private Decimal scale = 200;

    private RestClient restClient;

    private Guid lastTradeId = Guid.NewGuid();
    private List<Decimal> closingPrices = new List<Decimal>();

    public void Run()
        restClient = new RestClient(API_KEY, API_SECRET, API_URL);

@JustDave Where did you find this code snippet? This was valid for the very old version of the .NET SDK and of course, will not work nowadays.

You can check the most up-to-date samples in the SDK repository on GitHub.