Vodacom customer service sucks big time

I did an upgrade online for an i phone 13, received the phone but unfortunately the devise was faulty. I took it back to the vodacom shop, conpleted the forms required (which i have as proof) and waited for weeks for any response, after a few weeks i got response that the phone is woth the technical officers and no body could fix it, vodacom told me to file a complaint which i did and then they returned the contract and told me to take out a new device (contract) which i did again online, i received a working device but suddenly they billed me for the device that was returned to them now they suspended my account and i need to pay an outstanding amount of 16000 + after paying each month my phone bill! Somebody at vodacom did not do their work and now i.am the one to take the blame!! I am sorry after 20 years of being a loyal customer i can’t take this type of service anyomore.