TELKOM MOBILE - Defective phone on NEW contract

I have been a customer with telkom for years. I recently upgraded and soon after, the phone is giving issues. I am receiving calls however once answered, the calls cut off. I have notified Telkom of the issues on 20th May 2021. To date there is no feedback or correspondence. Case number ***. if this is not sorted out, I want this contract cancelled. They can take the phone back. I will go to another service provider. I am paying diligently for pathetic service and I need to be reimbursed for this.