PROOF OF PAYMENT

I installed the ADT system at my house early July 2014. I was told that I have to pay the admin fee of R385 which I paid on the 24 July 2014. To my surprise on the 25 July 2014 ADT debited R385 on my account and that caused me a reversal and the bank charged me R119. I phoned ADT and they requested the proof of payment. I forwarded the proof of payment on the 19/09/2014 at 13:25 to M Ramalitse and she confirmed that she has received it. On the 25/11/2014 I received a message again that I did not pay the R385, I resend the same proof of payment to W Bochele and she went to their statement and trace my proof of payment. She then confirmed that they have received payment. Today on the 19/02/2015, I received a message saying that my account is overdue I have to pay the same admin fee. I phone ADT again to tell them that I am not happy because they keep on sending me the same messages and I have to phone back at my expense to say the same thing again that I already paid the money. I was requested again to sent the proof of payment and this day I refused because they will come again saying that I did not made payment. Kindly assist me in resolving this matter this is just too much