STM32F407 bootloader flash error

[BlackSoalt]

hello, This article was written through a translator. The sentence can be strange because I can't speak English.

I am using stm32f407. I updated the firmware with an SD card to use the klipper.
However, there was a problem with the connection and I tried to install the initial firmware to start all over again.

I tried to update it by making various firmware, but it didn't respond. The firmware made by someone else didn't respond either.

So I tried to reinstall the bootloader.
I purchased STlink and updated the hex file with a dedicated program.

However, the firmware update using the SD card is still not working. And we're only printing these screens on the LCD.

We've already used 14 days to solve this phenomenon. Has anyone experienced the same problem as me?
I need your help. Help me, please.

[ByMalicious]

Did you solve the problem?