Mtn
Bad service and incompetent and no help

As I have done a upgrade on my account, my account has credit of R10 000!
And have paid my last month installment of R1250 and which means my credit is now at R8750 becAuse the payment does not reflect! Now they do not want to unlock my line cause they want me to pay R8750! But that is my credit! No one can help or willing to help or explain! Because they say in 10days I used R10 000 data on my account! But mtn store says that is what I can spend not what I must pay! But shows you the lack of knowledge and incompetence!