CELL C ***** - WHAT A JOKE!

CELL C WORST PROVIDER AND ***** DEPARTMENT AN ABSOLUTE JOKE! In 2017 we took a Fibre to the home and someone attached a sim card sneakily to the contract which we only found out after cancelling our Fibre. It is IMPOSSIBLE to get Cell C to get this sorted, after running around doing affidavits and whatnot, Cell C have now supposedly "never received" the documents. They also are such a joke I sat for 20 min waiting for ***** Dept to answer their phone! How do I get resolution to this and get my name off the blacklist which Cell C have placed me on!?