Worst service ever

I have a 120 free minutes per month as well as 300mb data and 500 sms.Every month I bring over minutes not used.I had over 200 minutes left and when I checked again there now is only 99 minutes.How to you justify this?They put up my account with R29 per month.I have not signed anything that gave them permission.So my minutes were just taken away and account just increased.Poor poor service been with this company for many many years but will never ever upgrade again.I will make it a point to tell all my friends and family about this poor service.And when I phoned the customer care a lady called Kaya gave me the worst service ever she has no people skills and are rude.She made me wait on the phone for more then 5 minutes to tell me my balance.When I asked her surname she refused to give it to me.Poor service.