Blacklisting Willy Nilly

My contract expired in Feb. I went to the store to renew my contract, but the device did not work correctly. I returned it within the 7 days, and waited for a week for a new phone. It never arrived, so i cancelled the entire contract and went to Cell C and got a device same day. I found out 6 months, when try to apply for a home loan, that I'm blacklisted because I haven't paid for the device from Telkom. I went back to the store and there is a clear note on the system that the device was returned. I've since had to collect proof, waybills, affidavits and many many many phones calls to their call centre. It's been 3 weeks and still no closer to being resolved. Not a single phone call or email from Telkom leading up to this. ***

Hopefully someone from Telkom will see this and take action.