The phone number of the SIM card is identical to the MSISDN of your card, but cannot be used for voice calls. If, for example, a device has to be configured via SMS, you can send AT commands to the MSISDN. SMS can be sent directly from the customer portal or via an API. For more details on the topic, visit https://help.1nce.com/dev-hub/docs/examples-mt-sms .