payment issues

I have been having a contact with cell c for 5years and always paying my payments never missed a payment , this couple of months I was billed a cancellation I have settled December 2018 and into April 2019 I was double debited I have called them for the past 2 weeks sent them the proof payment and one of their Team leader Letlhogonolo and he side he would take it to back office this was last week , no feedback apparently the back office was striking just saying if I have to res this debit order they would be the 1st ones to disconnect my network but they doesn't gave service