Pathetic customer service from Chatsworth Branch

I upgraded my contract at the Chatsworth store on 17 November 2020. I was assisted by a female staff member who had assisted in the conclusion of the contract with me. The contract was for a Samsung S20 Ultra, of which came with a R1000,00 accessory voucher. Since the conclusion of the contract of made various attempts at contacting the store assistant, left messages and she has not returned my call. According to a message she passed through another member of staff, my voucher was used for R399,00 for a screen guard which she had said she will replace with a proper one in the upcoming week when she receives stock. She was meant to contact me telephonically of which I am still waiting for the call. The balance of R600,00 from the voucher (according to her) will then be forfeited. When questioning why the balance is forfeited I did not receive answers. My screen guard has not, to date, been replaced and I have not received any sort of response from the Vodacom Chatsworth branch. This is absolutely pathetic customer service as far as I'm concerned. Sales staff don't respond to queries.. nobody knows what's going on there! Moving forward, Vodacom will no longer be my service provider.