Random debit of 1632

I am a Discovery Health Vitality member since 2011. My employer currently gets debited for my medical aid together with my Vitality. On the 1st of September 2015 an amount of R1632 was debited from my bank account. I have contacted Discovery Health on the 2nd of September 2015 to complain and find out what this is for and to get a refund. I received no warning of the amount to be debited. 5 phone calls to Discovery and they are still investigating what happened and I am no closer to receiving my R1632!!!