Dear Customer,

Thank you for taking interest in SureM!
MNC stands for Mobile Network Code, meaning the mobile carrier. You may check corresponding MNC codes using this website : http://mcc-mnc.com/
To know if the message can be sent to a certain number, please refer to the manual sent to your email to check the error codes.

Contact us at sureminternational@gmail.com if you face any more issues!
Thank you,
SureM