Handset problems

I upgraded my handset a year ago to a Vodafone Platinum 7. 6 months down the line it malfunctioned (restarted randomly and eventually got stuck in bootloop). Vodacom replaced it which took about 3 weeks. Now, another 6 months later, the exact same thing happened to the new handset. It seems to be a common problem of the specific device. I took it to Vodacare who advised me that the device will be replaced again, but they are out of stock and the waiting period is another 3 weeks. So in total i will be without a phone for almost 2 months of twelve, while paying for the phone. I lose business because of this. The loan phone i was given is not usable, it takes 4 minutes to just get into the contacts list, and another couple to get to a name. Impossible to use. I called the repair centre to speak to a manager that can help me but the consultant refused to put me through to one. After more than 22 years of being a Vodacom Custome i expect better service, and a working phone when i pay for one. I need a replacement phone, of the same specifications, that does NOT have a manufacturing fault and let me down for Month ever half a year.