Use Online Tool
Considering that the 1M(S) is very small and not easy to open, we provide an online tool to facilitate the ability to restore the factory firmware directly.
Video Demo:
This tool is based on esp-web-tools.
Resources
Factory Firmware File
With the ESP32C3 series used in the 1M, one of the easiest ways to flash the device is to use the WEB interface (https://web.esphome.io/) and select Firmware Refresh in there.
However, if the device has lost its USB driver, you will need to enter DFU mode to flash it.
You need to open the box, then power on the device, press and release the RST button at the same time as pressing the BOOT button, at this time, the two indicators show a slightly lighted state, then you can use the WEB flashing tool to flash in the factory firmware.
Other methods
esptool.py
If you prefer to use the command line tool, try this command:
esptool.py --chip esp32c3 --port /dev/tty.usbmodem* write_flash 0x0 factory-humen-sensor-1m_V230804_1.bin