Coflict Between Shorcuts And Keyevent?

I have a button with shortcuts is F5 Now i have a other textbox and code :

Private Sub RichTextBox2_KeyUp(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles txtdathanhtoan.KeyUp
ElseIf (e.Control = True AndAlso e.KeyCode = Keys.D6) Or e.KeyCode = Keys.F5 Then
txtdathanhtoan.Text = txtdathanhtoan.Text & "000000"
End If
End Sub

When above textbox focus. I PRESS F5 , but the button perform , textbox didn't perform.I want when i press F5 then FOCUSED Textbox perform not button.