The command uses only the IPC-DFU client bundled in the modem firmware ZIP archive to send commands to the running modem firmware. It does not trigger a modem firmware upgrade.
Make sure that the following requirements are met:
- The modem firmware in the ZIP archive matches the modem firmware on the device.
- The modem firmware on the device supports writing IMEI numbers.
Before writing, use the 91 imei-read command to check which IMEI slots are already written.