MTN refusing to take responsiblilty

My son lost his phone on the date 2014/04/ a Samsung S4 which was under contract and insured at the time. I reported the phone lost to the service center and later went to the Branch in Jabulani Mall notify them. I was asked to provide bank statements showing I had funds available in my account to show that I did have pay for the insurance at the time which I did and still MTN and 24hr Mobility refused to reimburse the phone after I gave them what they asked for. Both MTN and 24hr Mobility stated that I had stopped paying for insurance and the bank statements proves otherwise and I asked them to provide me with the prove that I had requested to cancel the insurance and they have failed to do so. I've been paying R449 since the phone got lost till now and I have been paying over a year and I don't have a phone that I am paying for is coming in a June 2015. I feel that I have been ****** by the provider because I paid for months on end and nobody ever go back to me or provide me with the info I requested. MTN and 24hr mobility have ****** me of thousands