unhappy cellphone insurance client

On August the 25th , I took a cellphone by the name Huawei Nova Y9a ,which debited almost R500[which included Insurance for the cellphone]. The debit orders for the cellphone continued at the same price until the 15th of August 2023 when it changed to R1603.11. I then went to Telkom in Florida, Johannesburg to complain where I was told that an employee by the name Zanele Ravhengani took a cellphone on my account using my details . I then confronted the above mentioned and she told me that she would pay me back ,which she did for only 2 months . Telkom did not cancel my account or her cellphones instead they continued debiting me this time it increased from R1603.11 to R1893.72 on the 15th of November 2023 which to this date has not been paid up. I want to ask why do employees have access to using customer details for their own personal use using customer confidential information