Weekly lines suspension due to payments not being allocated

I call them every week to unsuspend my lines. Apparently they changed systems and some payments we make aren't able to be allocated. I'm so sick and tired of MTN, really. Their agents don't even listen to what you explain to them, all that happens to is get smes after the calls you make to their call center about you having made arrangements to pay the amount due in 1 day, when you didn't even because you had already paid. I want MTN collections admin to call me and I need a formal apology for this harassment I have experienced in their hands for over 4 months now. When my contracts are all paid up, I will not be signing up for any further contracts with them and will not even recommend them to anyone!