Need help with MSI BIOS Flashback / CPU LED issue

Hi everyone, I really need help with my system.

I moved my SSD to the M.2_2 slot and added a new drive into M.2_1. I wanted to install Windows on the new drive, so I changed the boot priority to my USB flash drive. It didn’t boot, so I switched the boot priority back to the SSD in M.2_2 (the one with Windows). It booted fine at first, but then suddenly froze.

I forced a shutdown, and when I tried to turn it back on the CPU debug LED lit up.

I tried troubleshooting and decided to reflash the BIOS using the rear Flash BIOS button with a USB drive. But it’s not working: • I removed the board from the case, removed CPU/RAM/GPU, etc. • When I press the Flash BIOS button, the LED blinks slowly at first. • The motherboard powers on by itself, the CPU LED lights up, and then the Flash BIOS LED starts blinking fast. • It just keeps blinking forever and never finishes.

Has anyone run into this before? Am I missing something, or is my board’s Flashback feature just dead?