Why does it fail to return the firmware version after successful connection, and how to resolve it?​

[Longmasstime]

As you can see from the diagram, the UART is already connected, but the firmware version is not being returned.
looking forward to your reply:)

[Dimsmary]

The UART debug message confirms that the computer has successfully connected to the onboard USB-UART chip, specifically the CH340. However, the firmware version is returned by the ESP32—if the firmware is uploaded incorrectly, the version information will not be sent to the Open-STM software.