If you are using SmartConnect, you will need to use a specific APN depending on the application and the SIM color you have received. Please see the list below
SmartConnect Standard & Professional
SmartConnect (White SIM) - m2m005125.attz
SmartConnect (Yellow SIM)* - Broadband
SmartConnect Professional Plus - Point to Point Only
SmartConnect Professional Plus (Yellow SIM) - rover01.smartnetna.com
*Yellow SIMs are still supported for existing accounts, all new SIMs that are delivered for SmartConnect Standard and Professional must be White SIMs
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