Can-t-use-XmlSerializer-A-non-collectible-assembly-may-not-reference-a-collectible-assembly

CODE:

using WealthLab.Backtest;
using System;
using WealthLab.Core;
using WealthLab.Data;
using WealthLab.Indicators;
using System.Collections.Generic;
using System.Xml.Serialization;
using Steema.TeeChart;
using System.Windows.Documents;

namespace WealthScript1 
{   
    public class MyStrategy : UserStrategyBase
    {
        //create indicators and other objects here, this is executed prior to the main trading loop
        public override void Initialize(BarHistory bars)
        {
         XmlSerializer serializer = new XmlSerializer(typeof(TradeInfoList));
        }

        //execute the strategy rules here, this is executed once for each bar in the backtest history
        public override void Execute(BarHistory bars, int idx)
        {
            if (!HasOpenPosition(bars, PositionType.Long))
            {
                //code your buy conditions here
            }
            else
            {
                //code your sell conditions here
            }
        }

      //declare private variables below
    }

   public class TradeInfo2
   {
      public string Symbol { get; set; }
   }
   
   public class TradeInfoList
   {
      public List<TradeInfo2> TheList { get; set; } = new List<TradeInfo2>();
   }

}