Instructions:
1. Log into your device's WebUI.
2. Navigate to Network → Interfaces.
3. Press Edit on the mobile interface.
4. Untoggle / Toggle Auto APN. 
2. Navigate to Network → Interfaces.
3. Press Edit on the mobile interface.
4. Untoggle / Toggle Auto APN. Legacy WebUI
Auto APN is enabled by default. But if you have just inserted the SIM card you might need to restart (RUT9XX/RUT2XX) routers modem first (Status/Mobile/Mobile Information).
Instructions:
- Log into your device's WebUI.
- Navigate to Network → Mobile.
- Uncheck / Check Auto next to APN.
