/Error CS0534: 'AverageSummary' does not implement inherited abstract member 'SummaryStrategy.PrintSummary()' (CS0534) (Tk1)

I am not sure what the problem is and what it is that I am not doing


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Code:
base class :

using System;
using System.Drawing;

namespace Tk1
{
    public abstract class SummaryStrategy
    {
     

        public abstract void PrintSummary();


    }
}
THE CHILD CLASS
Code:
using System;
namespace Tk1
{
    public class AverageSummary:SummaryStrategy
    {
       
        private List<int> _asnumbers = new List<int>();
        public float Average;

        public AverageSummary(List<int> numbers)
        {

            Console.WriteLine("I am in AverageSummary");
            double sum = 0;

            foreach (var element in numbers)
            {
                sum += (double)element;
                _asnumbers.Add(element);
            }

            var avg = sum / numbers.Count();
            Average = (float)avg;
            //PrintAverage(numbers);
        }
       public void PrintAverage()//(List<int> numbers)
       {
        }
    }
}
THANK you