Remove duplicates from List only if last 2 elements are same

Question

I have a method :

         public List<Point> RemoveDuplicatePoints(List<Point> theVertices)
                {           
                        var aVertices = new List<Point>();
                        foreach (Point aPoint in theVertices)
                        {
                           
                            if ((int)theVertices.Last().X == (int)aPoint.X && (int)theVertices.Last().Y == (int)aPoint.Y)
                            {
                                continue;
                            }
        
                            aVertices.Add(aPoint);
                        }
        
                        aVertices.Add(new Point(theVertices.Last().X, theVertices.Last().Y));
                        return aVertices;
                    
                }
    

I want to remove duplicate from the list only if the last point is equal to previous point which is achieved from above RemoveDuplicatePoints(List theVertices) method.

Results :

1. a)Input list:

     List<Point> aLocalList = new List<Point>();
                         aLocalList.Add(new Point(387.238493723849, 645.502092050209));
                         aLocalList.Add(new Point(386.610878661088, 658.682008368201));
                         aLocalList.Add(new Point(148.744769874477, 951.150627615063));
                         aLocalList.Add(new Point(380.962343096234, 846.338912133891));
                         aLocalList.Add(new Point(478.870292887029, 741.52719665272));
                         aLocalList.Add(new Point(483.26359832636, 705.753138075314));
                         aLocalList.Add(new Point(483.26359832636, 705.753138075314));
   

 b)Output list has these points: this.RemoveDuplicatePoints(aLocalList);
                                //Expected result achieved
                                Point(387.238493723849, 645.502092050209);
                                Point(386.610878661088, 658.682008368201);
                                Point(148.744769874477, 951.150627615063);
                                Point(380.962343096234, 846.338912133891);
                                Point(478.870292887029, 741.52719665272);
                                Point(483.26359832636, 705.753138075314);



2) a)Input list:
           List<Point> aLocalList1 = new List<Point>();
                                    aLocalList.Add(new Point(387.238493723849, 645.502092050209));
                                    aLocalList.Add(new Point(386.610878661088, 658.682008368201));
                                    aLocalList.Add(new Point(148.744769874477, 951.150627615063));
                                    aLocalList.Add(new Point(380.962343096234, 846.338912133891));
                                    aLocalList.Add(new Point(478.870292887029, 741.52719665272));
                                    aLocalList.Add(new Point(483.26359832636, 705.753138075314));
                                    aLocalList.Add(new Point(148.744769874477, 951.150627615063));
       b) Output List has these points : this.RemoveDuplicatePoints(aLocalList1);
                                                   
                                    Point(387.238493723849, 645.502092050209);
                                    Point(386.610878661088, 658.682008368201);                        
                                    Point(380.962343096234, 846.338912133891);
                                    //Point(148.744769874477, 951.150627615063); is missing but its added at the end which is right
                                    Point(478.870292887029, 741.52719665272);
                                    Point(483.26359832636, 705.753138075314);
                                    Point(148.744769874477, 951.150627615063);
        

I want to remove the duplicate Point only if last two are same. If comparison happens between any other element in list except last() , the list element has to be retained. How to achieve this ?