after msgbox go to not answered groupbox (radiobutons) before continu with next macro

Hi there,

I'm new here and not very familiair with VBA.
I've searched on the internet for many days but can't find to solve my problem.

I've an Excel Workbook with several sheets.
A sheet named "Vragenlijst" contains 20 questions. Each question has 4 option buttons (Control Toolbox) in a group.

In the second sheet named "Controlevelden" the values of the 20 aswers are registered in colom B2 to B21.
In B27 i wrote a formula: =COUNT.IF(B2:B21;">0")>=20

After the questions are aswered there will be a summary of textual answers on the sheet named "Rapportage".

I have 1 command button proceeding all the actions neccesary. After pushing the button
a macro takes a picture (with 'camera'-option in Excel) of this summary and places it on a special place on sheet "Vragenlijst"

A MsgBox is giving me a box with "You didn't anwer 1 (or more) questions" when a question has not been answers (option button not chosen). When all the question are answered: "You answered all the question".

The problem is that after "You didn't asnwer 1 (or more) questions" it continues with the next macro in VBA.
I want to go to the not answered question before going further with the VBA command.

The command button has this code:

Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Me.ScrollArea = "A1:F132"
End Sub


Private Sub ComboBox1_Change()

End Sub

Private Sub commandbutton1_click()

checkvragen
foto
foto2
Macro2
Mail_workbook_Outlook_1
End Sub

the module (sub) 'checkvragen' has this code:

Option Explicit

Sub checkvragen()
    Dim rRange As Range
    Dim oCell As Variant
    Dim Counter As Long
    Dim Cancel As Integer
    Counter = 0
    Set rRange = Sheets("Controlevelden").Range("B2:B21")
    For Each oCell In rRange
        If oCell.Value = 0 Then
            Counter = Counter + 1
        End If
    Next
    If Counter <> 0 Then
        MsgBox "U heeft  " & Counter & "  vraag/vragen nog niet beantwoord."
        Else: MsgBox "U heeft alle vragen beantwoord."
        Cancel = True
        End If
End Sub

Can anyone help me please?