Iphone 12pro faulty with no after service

I Purchased 2 iPhone 12 pro's which has exactly the same problem : Apple logo flashing at start up. I took both of them to the Vodashop in centurion, where they tried software restore and reload which made no difference. I then took them to the Istore in Centurion where they also tried to restore the phones and reload software where once again this was not sorted, so they gave me a report on both saying that it is a hardware issue. The problem I have is that the Vodashop wants to send in my iPhone to the repair centre which may take up to 21 days!!! and then I run the risk of getting a Exchange unit or may unit to be opened and repaired, which is unacceptable as I paid top Dollar for a New "Boxed" iPhone which seems to have a hardware issue. No one can help me or give me some sort of proof that I had an out of box failure that was reported within my 7days cool down period. I have been in contact with "Apple support" international and wasted hours on the phone only to hear they are aware of the problem and their engineers are working on it. It is after a lot of research and time spent that the conclusion is that the specific 2nd batch of iPhones have some sort of hardware issue, as the first batch(November 2020) do not have this issue. I now write a Hellopeter as there is no one I can contact who can assure me that if the next software update from apple does not resolve the issue, my phones will be exchanged with brand new boxed units. Please help vodacom.