Telkom fix this

Telkom since 2020 we been having a problem, I ordered a phone they delivered a wrong handset, tried for them to pick it up but nothing, in December I was helped by the manager at waterfall mall Rustenburg to return the phone after months of promises from Telkom online to come pick up the handset, yesterday I went to Telkom and to my surprise I owe you guys 14500 for a handset that's been couriered back to you😠? How do I owe soothing that you have?