Before typing secret codes, you must understand the stakes.
If your MT6580 device is rooted (Magisk or SuperSU), you do not need secret dialer codes. mt6580 imei repair code
This method works on 90% of rooted MT6580 phones, bypassing dialer restrictions. Before typing secret codes, you must understand the stakes
The Crucial Warning: This Engineer Mode method only works if your NVRAM is partially intact. If you have completely wiped the NVRAM or damaged the partition, the code will appear to work, but the IMEI will revert to null on reboot. This method works on 90% of rooted MT6580
Moreover, in many Android 6, 7, or 8 (Go edition) MT6580 builds, manufacturers have disabled the AT+EGMR write command for security. In that case, the code does nothing.