problem with retrieving value from Indicator in cbot

Hi,

Indicator RSI_xMA_onChart:
        public string buySellValue = "";

            buySellValue = signT;

Now I want to get value from indicator in robot like that: 
using System;
using System.Linq;
using cAlgo.API;
using cAlgo.API.Indicators;
using cAlgo.API.Internals;
using cAlgo.Indicators;

namespace cAlgo.Robots
{
    [Robot(TimeZone = TimeZones.UTC, AccessRights = AccessRights.None)]
    public class NewcBot : Robot
    {

        private RSI_xMA_onChart newIndicator;

        protected override void OnStart()
        {
            newIndicator = Indicators.GetIndicator<RSI_xMA_onChart>();

            //   Print(sma.buySellValue);

        }

        protected override void OnTick()
        {
            // Put your core logic here
        }

        protected override void OnStop()
        {
            // Put your deinitialization logic here
        }
    }
}

I got:
New cBot (5), EURUSD, h1 | Crashed in OnStart with ArgumentException: Incorrect parameters count. Parameter name: parameterValues