Sent to debtors without any knowledge

My husband took out a contract for WiFi. Due to him losing his job we were unable to pay for a few months. Fast forward we went to the Gate way branch to settle our balance. The gentleman who assisted us adviced us that nothing is showings on their side. We called their call centre to confirm because we know how *********** Telkom staff.is and they too confirmed what the consultant at the branch said. Now we received zero communication from Telkom until now when we receive a letter from the Debt Collection company for R5000. I am not going to pay that amount when Telkom failed to notify us that we owe them. I am so livid!!!! I need to speak to someone about this as I cannot call the call centre nor speak to branch consultants cause they themselves are clueless