I can't make voice calls with EM12-G

hi,nshi9:
I have confirmed that the modem in your device supports voice dialing, but currently your SIM card provider or operator does not support voice calling for this type of modem. If you need to use voice calling function, you can change to another operator to try it.

+COPS: 0,0,“NTT DOCOMO NTT DOCOMO”,7