Chart-disappears-when-changing-Style-of-custom-Indicator

Hi everyone,

I've created this simple indicator and when I add it to a chart, it works fine. However, I encounter an issue when I try to modify its style, such as changing the color or thickness. Every time I attempt to make these adjustments, the entire chart disappears, as shown in the attached image. Has anyone else experienced this? Any suggestions on how to fix it would be greatly appreciated.

Thanks in advance!

CODE:
using System.Diagnostics;
using WealthLab.Core;
using WealthLab.Indicators;
namespace WLLibrary2;

public class Close : IndicatorBase
{

    public override string Name => "Close";
    public override string Abbreviation => "Close";
    public override string HelpDescription => "Draw a line at the close of each bar.";
    public override string PaneTag => "Price";

    public override bool IsSmoother => false;

    protected override void GenerateParameters()
    {
        AddParameter("Source", ParameterType.BarHistory, null);
    }

    public Close()
        : base() { }

    public Close(BarHistory source)
        : base()
    {
        Parameters[0].Value = source;
        Populate();
    }

    public static Close Series(BarHistory source)
    {
        var key = CacheKey(nameof(Close));
        if (source.Cache.ContainsKey(key))
        {
            return (Close)source.Cache[key];
        }
        var close = new Close(source);
        source.Cache[key] = close;
        return close;
    }
    

    public override void Populate()
    {
        var source = Parameters[0].AsBarHistory;
        DateTimes = source.DateTimes;
        Values = source.Close.Values;
    }

}