Query on billing amounts

I completed an upgrade on my cell phone and account for ********** 171, I was told that the Samsung J5 would cost R289 pm going forward and not R442 pm, I specifically requested that the insurance not be included in the monthly billing, yet every month I'm still billed for the Insurance, also, I do not receive my monthly invoices, but the debit order has remained the same for the account, I assumed it would be less, the once off fee has already been debited from my account and I've even emailed Glocell and still have not received any feedback from them pertaining to my account queries. This is disgusting service.