Flashing the firmware is a sensitive process. When doing so, you need to make sure that the instructions found here are followed to the T.
If you weren't able to flash the firmware correctly, it may say "No bootloader found".
"No bootloader found" means that the keyboard is not getting into bootloader mode at the correct time, or it's not getting into bootloader mode at all.
When your Raise is in bootloader mode, the Neuron's LED pulses blue (increases and decreases blue light intensity alternatively).
If your Raise is stuck in bootloader mode, close Bazecor, open it again, and follow the steps on screen to flash your Neuron's firmware.
If you're trying to get your Raise into bootloader mode to flash the firmware, but your Raise isn't doing it (Neuron never pulses blue, and Bazecor just says "No bootloader found"), then try this: