The following source-code implements the K-means algorithm but im getting pointcollection errors

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

namespace ConsoleApplication10
{
	class Program
	{

		static void Main(string[] args)
		{
		}

		public static List DoKMeans(PointCollection points, int clusterCount)
		{


			List allClusters = new List();


			List> allGroups = ListUtility.SplitList(points, clusterCount);


			foreach (List group in allGroups)
			{

				PointCollection cluster = new PointCollection();

				cluster.AddRange(group);

				allClusters.Add(cluster);

			}



			int movements = 1;

			while (movements > 0)
			{

				movements = 0;


				foreach (PointCollection cluster in allClusters)
				{

					for (int pointIndex = 0; pointIndex < cluster.Count; pointIndex++)
					{

						Point point = cluster[pointIndex];

						int nearestCluster = FindNearestCluster(allClusters, point);

						if (nearestCluster != allClusters.IndexOf(cluster))

						if (cluster.Count > 1)
						{

							Point removedPoint = cluster.RemovePoint(point);

							allClusters[nearestCluster].AddPoint(removedPoint);

							movements += 1;

						}

					}

				}

			}

		}

		return allClusters;

	}

}