The Grandstream GXW-4000 series, and Grandstream HT81X series ATA's use a different code structure than other Grandstream devices; they must be provisioned as 'Gateways' in NDP. This article explains how to provision these devices.1. In the PBX Portal, add a phone to a user (via the 'Add Phone' button) and select the appropriate Grandstream phone model.The 'm' suffix is reserved for ReachUC.  Using the 'm' suffix for a non-ReachUC device may cause issues.2. In your reseller Dashboard navigate to Manage NDP. Inside of NDP select configuration > Gateways.3. Click on Add configuration and populate the required fields.4. Navigate to the Grandstream HT's GUI, select Advanced. 5. Set the Firmware Upgrade and Provisioning setting to HTTP6. Set the Config Server Path to sipcfg.io/cfg/7. Save the settings and restart/reprovision the device. After the device is done reprovisioning it should have pulled the user information assigned to the device in NDP and be registered with the Skyswitch platform.