bad service received from MTN

Contract was upgraded by MONDO Online Agent, for a certain amount which I agreed to. MTN Billing department charged me another amount which I NEVER agreed to. Emails sent to *** and *** and even NFSO (apparent Ombudsman's) over the last 3 months have been unresolved.

My phone service has been suspended due to non payment.

I refuse to pay an amount to which I never agreed to.

Very unhappy client and very bad service received from "MTN service champions"