Custom indicator works on inactive charts but fails on active ones

I've been working on this for a few days and I can't seem to understand which part of my code is wrong, also new to ctrader and c#.

currently, the GBPUSD chart is inactive and so the indicator is working -

But on the BTCUSD chart which is currently active, it stops working - 

Here is the code -

using System;
using cAlgo.API;
using cAlgo.API.Internals;
using cAlgo.API.Indicators;
using System.Collections.Generic;
using cAlgo.Indicators;

namespace cAlgo
{
    [Indicator(IsOverlay = true, AutoRescale = true, TimeZone = TimeZones.UTC, AccessRights = AccessRights.None)]
    public class Renko2 : Indicator
    {

        [Parameter("Number of Pips", DefaultValue = 10)]
        public int Number_Of_Pips { get; set; }

        [Output("Close Price", LineColor = "Red", Thickness = 5, PlotType = PlotType.Points)]
        public IndicatorDataSeries Latest_Close { get; set; }

        [Output("Open", LineColor = "Green", Thickness = 5, PlotType = PlotType.Line)]
        public IndicatorDataSeries Bricks_Open { get; set; }

        [Output("Close", LineColor = "Red", Thickness = 5, PlotType = PlotType.Line)]
        public IndicatorDataSeries Bricks_Close { get; set; }


        public bool first_brick_added;
        public bool brick_added;

        public int prev_index;

        public double first_brick_open;
        public double previous_brick_open;
        public double previous_brick_close;
        public double closed_candle_price;
        public double pips_digits;
        public double pips_close;


        public class Renko_Brick
        {
            public double Brick_Open { get; set; }
            public double Brick_Close { get; set; }
        }

        public List<Renko_Brick> Bricks = new List<Renko_Brick>();




        public void first_brick()
        {

            if (closed_candle_price >= (first_brick_open + pips_digits))
            {
                // ADD FIRST BULL BRICK
                Bricks.Add(new Renko_Brick 
                {
                    Brick_Open = first_brick_open,
                    Brick_Close = first_brick_open + pips_digits

                });

                first_brick_added = true;
                
            }


            if (closed_candle_price <= (first_brick_open - pips_digits))
            {
                // ADD NEW BEAR BRICK
                Bricks.Add(new Renko_Brick 
                {
                    Brick_Open = first_brick_open,
                    Brick_Close = first_brick_open - pips_digits

                });

                first_brick_added = true;
                
            }


            if (!(closed_candle_price >= (first_brick_open + pips_digits)) && !(closed_candle_price <= (first_brick_open - pips_digits)))
            {
                first_brick_added = false;
            }

        }




        public void add_a_brick()
        {

            if (closed_candle_price >= previous_brick_close + pips_digits)
            {
                // ADD BULL BRICK
                Bricks.Add(new Renko_Brick 
                {
                    Brick_Open = previous_brick_close,
                    Brick_Close = previous_brick_close + pips_digits
                });
                return;
            }


            if (closed_candle_price <= previous_brick_close - pips_digits)
            {
                // ADD BEAR BRICK
                Bricks.Add(new Renko_Brick 
                {
                    Brick_Open = previous_brick_close,
                    Brick_Close = previous_brick_close - pips_digits
                });
                return;
            }


            if (!(closed_candle_price >= (previous_brick_close + pips_digits)) && !(closed_candle_price <= (previous_brick_close - pips_digits)))
            {
                Bricks.Add(new Renko_Brick 
                {
                    Brick_Open = previous_brick_open,
                    Brick_Close = previous_brick_close
                });
                return;
            }

        }



        private void OnBarClosed(int index)
        {
            closed_candle_price = Bars.ClosePrices[index];
            Latest_Close[index] = closed_candle_price;


            if (!first_brick_added)
            {
                Print("index {0}, prev_index {1}", index + 1, index);
                first_brick();
            }
            else if (first_brick_added && Bricks.Count > 0)
            {
                previous_brick_open = Bricks[Bricks.Count - 1].Brick_Open;
                previous_brick_close = Bricks[Bricks.Count - 1].Brick_Close;

                add_a_brick();

                Bricks_Open[index] = previous_brick_open;
                Bricks_Close[index] = previous_brick_close;

            }
        }

        private int lastIndex = 0;


        protected override void Initialize()
        {
            pips_digits = Number_Of_Pips * Symbol.PipSize;
            first_brick_added = false;
            first_brick_open = Bars.OpenPrices[0];

        }


        public override void Calculate(int index)
        {

            if (index > lastIndex)
            {
                OnBarClosed(lastIndex);
                lastIndex = index;
            }




        }
    }

}

After the historical bars , I want the Calculate() method to be run on every closed bar to check if the closing price is higher than the previous brick close by the number of pips (add a new higher brick), lower than the previous brick close by the number of pips (add a new lower brick) or if the closing price does not meet the minimum pip level add a new brick on the same level as the previous brick.

I hope this makes sense

Kind Regards