If your phone is working and you are using a legitimate SIM card, your IMEI is perfectly fine. Changing it would only cause problems, potentially leading to a "Contact Service" error or the phone being unable to register on any cellular network. You would be turning a functional phone into a non-functional one.
*#7370# (Requires entering the security code) nokia 105 ta 1203 imei change code
The concept of an IMEI change code might be more related to smartphones or more advanced mobile devices where customization and alteration of device identifiers are sometimes sought after by advanced users. For basic phones like the Nokia 105, changing the IMEI is not a straightforward process and generally not recommended. If your phone is working and you are