Does not have the capability to resolve a problem, empty promises

I have been a loyal Vodacom client for ages. I made the mistake of renewing my Vodacom contract end of last year… I have send my iPhone 8 in for repairs 3 times and all 3 times it is manufactory faults or operating systems that does not work. My phone loose signal something none of my previous phones did and my battery does not even last have a day. My calls drop regular in a day at least 3 times is that what I am paying for? I have escalated this matter each time but still they can’t resolve this matter the CCM person words was we will give you a new phone out of good faith because they cannot find any fault, so I got a new phone with some ells sim card still on it... so how new was this phone? And most ironically the new phone just enhanced the problems I experienced, maybe this phone was faulty as well because why will there be a sim card in the phone and the phone gives trouble? Until now I never experience any issue with Vodacom or my previous 4 iPhones I had. I just want to know what must I do to get it resolve and get what I am paying for. TCF,Ombud I don’t know because everyone promises and it is empty promises