Where is my invoice!?

<p>I usually receive my monthly invoice from MTN by around the 29th or 30th of every month – via e-mail. I have still not received my invoice for the month of September 2016 – ending 26 September 2016. I have sent TWO e-mails to Mtn's Customer Services. They sent automated responses, including a reference number after my first e-mail: # ********** 4 - but, still no invoice, no explanation. O yes, they have taken the usual chunk of money from me ...</p>