Homework Assistance Needed

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Question number 7: Movie Ticket Solution

I have coded with the following; however, the price field remains blank after I have coded the btnIf. Here is my code:
Private Sub btnIf_Click(sender As Object, e As EventArgs) Handles btnIf.Click
Dim txtAge As Integer
Dim lblPrice As Integer

If txtAge < 3 Then
lblPrice = 0

ElseIf txtAge > 3 Then
lblPrice = 9

ElseIf txtAge < 64 Then
lblPrice = 9

ElseIf txtAge < 65 Then
lblPrice = 6

End If

End Sub