unnecessary calls

I paid my account on the 28/02/2015 via Fnb atm amount of R200.00 and Monday on the 2/03/15 I got a call from the lady at Nimble Group advising me she doesn't see the payment I made,and i told her that I made the payment on the 28/02/15. Then last night at around past 8 on the 4/03/15 I received a call from another lady requesting me same thing and I got very annoyed and told her she must check clearly and she finally saw the payment and advised was appeared on their side on the 2/03/15 and I even told her that I know you are going to charge this calls and she wanted to say no.however she ended admitting that. So now this morning on the 5/03/15 i received another call and tell the lady you cant call me again cos i am gonna be charged again. My query is I get unnecessary calls and i am gonna be charged by them and they must reverse them<br> Matshidiso Deka