MTN not answering calls

I have called MTN in the beginning of May to cancel my contract and was informed it would be cancelled and my last payment will be in June 2015. In the beginning of June I sent an email requesting cancellation just to make sure I had something in writing, making sure it was 30 days notice. On the 22nd of June I received and email from MTN saying sorry for the late reply and here's a document to fill out to cancel your contract. I filled it out however I have already been informed that the contract would be cancelled and the late response is completely unacceptable. In June I will make my last payment and there will be no further payments made to MTN whatsoever. I have tried to call the 808 number and I hold for 2 hours and then they drop the call. I haven't been able to through to anyone all month. All I want is verification of my last payment amount and also that the contract will be cancelled. I really didn't want to resort to Hello Peter but what other choice do I have if I'm not being assisted? I really want to remain and MTN subscriber and keep my number on a prepaid line but I'm seriously reconsidering remaining loyal to a service provider who is not loyal to me. Please help!