triple charged for showmax

I was double charged for showmax in the month of December.I called DSTV callcentre to notify them about my problem in January.Since I was using my cellphone the call cost me more than the R99 X2 that I was charged so calling again is not an option for me.The callcentre gentleman promised that they will look at my query.He said that maybe I was using different usernames to access my account (which is possible but should not be allowed then if its problematic).Even if that is the issue, I only have 2 email addresses so I can only access my account with only 2 different username but I as charge for 3 instances for which 1 was discounted.