Dude, I'm also having that problem. Mine has stock firmware at 202305something so I've downloaded OnionOS 2,4-RC, formatted a SanDisk 64GB microsd as FAT32 using guiformat and all goes well during the installation of OnionOS. However, once the system reboots, I get Miyoo splash boot screen and the console freezes. I have already reformatted the microsd, copied the files over and went through the installation process but the same problem happened again.
Any clues what could be the issue?