If the flash button remains lit and stops it means there is an issue.
Correct format is FAT32 and the renamed file should be on it's own.
Most common issues are Faulty USB or not formatted correctly.
Bios file not renamed correctly(depends on which MB)
USB not inserted into the correct USB port. (depends on which MB)It is recommended to use the USB 3.2 Gen 1 Port (Q-Flash Plus Port) for flashback.
Review your MB manual page 12 for flashback on the rear I/O panel.
This method only needs power to the MB so the system should be shut down.
There is another Bios update method when you can access Bios.
Hope this helps👍