A common problem after flashing a new ROM or performing a factory reset is the "Invalid IMEI" error, which prevents the phone from making calls or connecting to data.

Select the "IMEI Download" option and enter the 15 digits found on your device's physical label.

: An online platform for IMEI checking that identifies device specifications, warranty status, and blacklist information . How to Fix "Invalid IMEI" After a Hard Reset

Click to write the IMEI back to the device's permanent memory. Fixing Connectivity Issues Post-Reset