I have cancelled my contract but i was debited

Good day,<br> <br> I called in sometime last week requesting for my invoice, I spoke to 3 different agents who promised to send me my invoice and none of them was able to. I then called in to cancel my service because I thought to myself, if tracker is unable to send a stupid thing as an invoice, God knows what will happen if my car can be ******. I then spoke to Tshepiso Ledwaba from Retentions who did not even bother to retain and understand my reason for cancellation. she assured me that my services were cancelled. When I asked her if she was not interested in retaining me, she dropped the line on my ears. <br> <br> I spoke to her team leader Nkosana who was very helpful and managed to send my invoice. He as well confirmed that my services are cancelled.<br> <br> I was surprised when my debit order went through on my bank account. Why did you debit my account if my services have been cancelled. I want back my money!!!!!!