I was following the steps provided on official website but the COM port is lost after completing all steps for Aruduino Lab for Micropython. First I upload Nano33_updateBLandSoftDevice but board doesn't go automatically in bootloader mode as mentioned in sketch. I need to manually put board in bootloader with double press on reset button.
Further, I use bossac program to upload latest firmware (ARDUINO_NANO_33_BLE_SENSE-20240105-v1.22.1.bin) from Arduino micropython official webiste. Upon completion of this step the COM port is lost.
Without a port, the Arduino Lab for Micropython can't be used. I made this working on my first try few months ago but the similar steps are not working anymore.