What's wrong with my code visual basic 2010?

I wrote this code and i'm trying to make it say "Please CHOOSE A CELL PHONE!" if you do not click on one of the radiobuttons this is what i wrote:

Public Class Form2
Dim price As Double
Private Sub RadioButton1_CheckedChanged(ByVal sender As System. Object, ByVal e As System. EventArgs) Handles RadioButton1. CheckedChanged
If RadioButton1. Checked = True Then
PictureBox1.Image = System. Drawing.Image.FromFile("C:\Users\… One.png")
price = 299

ElseIf RadioButton2. Checked = True Then
PictureBox1.Image = System. Drawing.Image.FromFile("C:\Users\… Galaxy 4.jpg")
price = 349

End If
End Sub

Private Sub RadioButton3_CheckedChanged(ByVal sender As System. Object, ByVal e As System. EventArgs) Handles RadioButton3. CheckedChanged
If RadioButton3. Checked = True Then
PictureBox1.Image = System. Drawing.Image.FromFile("C:\Users\… 5.jpg")
price = 500

ElseIf RadioButton4. Checked = True Then
PictureBox1.Image = System. Drawing.Image.FromFile("C:\Users\… Venice.jpg")
price = 219

End If
End Sub

Private Sub Button2_Click(ByVal sender As System. Object, ByVal e As System. EventArgs) Handles Button2. Click
If RadioButton1. Checked = False Then
MessageBox.Show("Please choose a cell phone!")

ElseIf RadioButton2. Checked = False Then
MessageBox.Show("Please choose a cell phone!")

ElseIf RadioButton3. Checked = False Then
MessageBox.Show("Please choose a cell phone!")

ElseIf RadioButton4. Checked = False Then
MessageBox.Show("Please choose a cell phone!")

Else
form3.show()
End If
End Sub
End Class

In your Button2 click event, change the first part of your IF Statement as follows:

If RadioButton1. Checked = False and If RadioButton2. Checked = False _
and If RadioButton3. Checked = False and If RadioButton4. Checked = False Then
MessageBox.Show("Please choose a cell phone!")