Suspended but account is up to date

My account has been suspended stating that I am in arrears whereas I am not. Call centre confirmed that my account is up to date stating that the fault is on Telkom's side. Have been calling since beginning of the month and was told I do not have anything to worry about. Tried doing an upgrade and was declined due to my account being in "arrears". I need this sorted out ASAP. It is unacceptable. The amount that Telkom says I am in arrears is the same amount as is due end of this month. Now this is going to have an impact on my credit record and my upgrades and this is unacceptable. Can this be sorted out and my upgrade get done ASAP as my account is up to date and Telkom made a mistake on the billing side.