Hello, after the administrator adds the enterprise employee, if the staff has not registered DingTalk, you can see in the admin panel (oa.dingtalk.com) contacts interface that “There are x unactivated members in your organization, Activation Notification”, click on the "Invite" botton after the employee, or click [Activation Notification] - [Send Activation SMS], you can send an activation SMS to the employee. If you do not click Send, the activation SMS will not be sent.
In addition, if you need to enable/disable automatic transmission activation SMS, you can open it in [Admin Panel] - [Contacts] - [There are x unactivated members in your organization, Activation Notification] - turn on/off [Automatic activation messages].