Supervisor Asanda from Merchants refused to speak to me.

I purchased prepaid airtime of which the ninth digit was not printed clearly on the slip. I contacted vodacom call centre and spoke to Slindile at 4:10 pm on the 4th May 2018. She asked me for a serial number but I could only find a voucher number of which the last digit was unclear. She requested me to go back to the store which is 40 km away. I requested to talk to the supervisor at which Slindile responded that he is busy with another agent and she will get him/her to call me back. At 5:06 pm Slindile called me back stating that her supervisor refuses to talk to me. Supervisors name is Asanda and they are from the Merchants call centre. Very bad customer service from Asanda. Listen to your recordings and resolve.