My mobile number is giving me problems

On the 21st December 2015 I reported to vodacom through their customer number 111 of my network problem. They initially recommended that I reboot the phone and maybe then it will function properly. Afterwards it still gave me problems, again I reported and they indicated that maybe it might be the gadget itself ( phone), I changed the phone however the problem persisted. On the 28th December they allocated me a service request number : S3-9PS27-75001. However the problem is still persistent and every time I call the customer number they are unable to exactly tell me what the actual problem is and by when it will be resolved. In summary I am unable to make calls as whoever I call is unable to hear me and also if it does happen the phone cut in the middle of a call. I have been literally calling them everyday without any much success and I am not being referred to the actual division dealing with my network problem as they have indicated.