Exception-executing-GetOptionsSymbol

The code above works fine. The problem occurs when you call GetHistory(). It would be easy to pinpoint with a full (minimal) example that exhibits the error.

Sorry, the issue in this case is the method OptionSynthetic.GetHistory()

Tested on IBM, most recent N years: 1

CODE:

using WealthLab.Backtest;
using System;
using WealthLab.Core;
using WealthLab.Indicators;

namespace WealthScript4 
{
    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)
        {
         StartIndex = bars.Count - 1;
        }


        //execute the strategy rules here, this is executed once for each bar in the backtest history
        public override void Execute(BarHistory bars, int idx)
        {
         double underlyingPriceShort = 180.5;

         String oSynShort = OptionSynthetic.GetOptionsSymbol(bars, OptionType.Put, underlyingPriceShort, bars.DateTimes[idx], minDaysAhead: 40, allowExpired: true, priceIsStrike: true);
         
         //why is a strike of 180.5 not possible?
         BarHistory oBars = OptionSynthetic.GetHistory(bars, oSynShort, iv: 0.4);
        }      
    }
}

Exception:
Execute Exception (IBM,249) Line 27 - The input string '180.5' was not in a correct format.
at System.Number.ThrowFormatException[TChar](ReadOnlySpan`1 value)
at WealthLab.Backtest.OptionsHelper.ParseSymbol(String symbol)
at WealthLab.Backtest.OptionSynthetic.GetHistory(BarHistory underlier, String optionSymbol, Double iv)
at WealthScript4.MyStrategy.Execute(BarHistory bars, Int32 idx) in :line 27
at WealthLab.Backtest.UserStrategyExecutor.InitGetter(List`1 lst, DateTime dt)

Correct, I have german settings on PC: