Harassment

My second complaint in 5 months regarding bad service from you . my payment method KwikServe is convenient for me which was never the problem, A debit was due for 31.08.2015 and got confirmation SMS of this arrangement .when I received a reminder sms on the 4.09.2015 to pay my account I then called to query what happened ,to find out the debit never went off. Up until today a cannot seem to get a valid reason from you guys as to why this is .i was then told that a supervisor advised that when using this method I should get a call confirming payment whenever I use the ussd which i never did ever since using this option .This is new to me and also that this payment option could give problems however should pay cash .A repeat debit was set for the 1.10.2015 as nothing sooner can be done .i get a call yesterday from collections for payment , I explain my story and escalated to customer service which to me seems it was not because I got another call today for collections. you don't debit my account and cannot provide reason ,this reflects bad on my ITC and still harassing me for money you failed to debit and telling me what payment option to use. Pathetic service