TreeMap put is not working as expected

class Point{
    int x, y, l;

    Point(int x, int y, int l){
        this.x =x;
        this.y =y;
        this.l=l;
    }
    @Override
    public int hashCode() {
        return y;
    }

    @Override
    public boolean equals(final Object obj) {
        if(this == obj) return true;
        if(!(obj instanceof Point)) return false;
        Point p = (Point) obj;
        return this.x == p.x && this.y == p.y;
    }
}

    TreeMap<Point,Integer>  sortedMap = new TreeMap<>((p1, p2)-> p1.l-p2.l);
    sortedMap.put(new Point(4,5,0),0);
    sortedMap.put(new Point(5,5,0),6);
    System.out.println(sortedMap.size()); -> Output:  1
    System.out.println((new Point(4,5,0)).equals(new Point(5,5,0))); -> Output -> False.

I have overloaded both hashcode, equals method in class. I think put method should use equals method to determine whether the same object exits or not. But it is not working as expected.

I am not sure why my hashMap size is 1. Please let me know if I understood hashmap working wrongly. Help me to identify bug in this code ?