Account still being struck after account closure

I cancelled my Vodacom contract (and made the huge penalty payment) and received confirmation that it was cancelled 18 May. However my bank account still got struck for the June payment. I logged a request for refund and received this mail:

we trust you enjoyed the service experience. Your query with ref number *** has been closed.

No communication on what was done, and no refund processed. So basically closing query without resolution.