Common causes of IMEI loss:
Before attempting a repair, it is crucial to understand that an IMEI is the digital fingerprint of your smartphone. In many jurisdictions, including the United States, United Kingdom, and European Union,
This is a temporary repair. A single factory reset will wipe the IMEI again. Moreover, a single wrong AT command can hard-brick the modem.
adb shell su setprop sys.usb.config diag,adb