This was all about VIVAZ PRO. There is a big difference between those two phones. If you mean VIVAZ PRO: Yes there is only the method to use payable software or by paying a fee to use the method a flashing/unlocking.
While VIVAZ (solo) may be flashed on another way. Found so many manuals on the internet, which worked for 99% of the users. Search for 'debranding vivaz'.
Greets, Dimi