Диаграмму невозможно закрыть с первого клика

#include <vcl.h> 
#include <math.h> 
#pragma hdrstop 
 
#include "Unit2.h" 
#include "Unit1.h" 
//---------------------------------------------------------------------------
#pragma package(smart_init) 
#pragma resource "*.dfm" 
TForm2 *Form2; 
//---------------------------------------------------------------------------
__fastcall TForm2::TForm2(TComponent* Owner) 
: TForm(Owner) 
{ 
} 
//---------------------------------------------------------------------------
float i[3]; 
float u[3]; 
int step=0; 
int points = 200; 
void __fastcall TForm2::FormActivate(TObject *Sender) 
{ 
float I1 = StrToFloat(Form1->StringGrid4->Cells[1][1]), 
I2 = StrToFloat(Form1->StringGrid4->Cells[2][1]), 
I3 = StrToFloat(Form1->StringGrid4->Cells[3][1]); 
int j = ComboBox1->ItemIndex; 
if(j == 0) 
{ i[0] = I1; i[1] = I2; i[2] = I3; Series1->Title="I1"; Series2->Title="I2"; Series3->Title="I3";} 
if(j == 1) 
{ i[0] = I3; i[1] = I2; i[2] = I1; Series1->Title="I3"; Series2->Title="I2"; Series3->Title="I1";} 
Series1->Clear(); 
Series2->Clear(); // построитель графиков 
Series3->Clear(); 
float vT = 2*M_PI /points; 
float phase = StrToFloat(Form1->DBGrid1->Fields[11]->AsString); 
for(int pnt=0;pnt<points;pnt++)>AddXY(vT*pnt+step, i[0]*ph, "", clBlue); 
Series2->AddXY(vT*pnt+step, i[1]*ph, "", clRed); 
Series3->AddXY(vT*pnt+step, i[2]*ph, "", clGreen); 
} 
step++; 
 
} 
//---------------------------------------------------------------------------
void __fastcall TForm2::Button3Click(TObject *Sender) 
{step = 0; 
Button2 -> Click(); 
Close();