Unhandled Exception: System.FormatException: Input string was not in a correct format. Please answer where is my mistake

Question

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

    namespace EX_02_04
    {
        public class Program
        {
            static void Main(string[] args)
            {
                int hexNum = 2015;
                Console.WriteLine("|0x{0,-8:X|", hexNum);
                double fractNum = -1.856;
                Console.WriteLine("|0,-10:f2}|", fractNum);
            }
        }
    }

When I am running this code, facing some error like below:

Unhandled Exception: System.FormatException: Input string was not in a correct format.

at System.Text.StringBuilder.AppendFormatHelper(IFormatProvider provider, String format, ParamsArray args)
at System.String.FormatHelper(IFormatProvider provider, String format, ParamsArray args)
at System.IO.TextWriter.WriteLine(String format, Object arg0)
at System.IO.TextWriter.SyncTextWriter.WriteLine(String format, Object arg0)
at System.Console.WriteLine(String format, Object arg0)

Can you please answer me where the problem in the code is?