Which software and radio firmware versions are you using?
Had the module worked perfectly with the same SIM before? If yes, did you take any new settings?
Could you help to share to me the log of AT+COPS? command?
There are a lot of things that can happen when LX60 and RV55 don’t attach to the network.
Please check band support, SIM card, APN, radio firmware, signal network.
You can try to reset the AirLink gateway to the factory default settings.
- Backup your device settings by downloading and saving the template. Please refer to page 20 in 41113548_ALEOS 4.13.0 Software Configuration User Guide for AirLink LX60_r1.pdf for more details.
- Reset the device to factory default settings. Select reset mode: Preserve Only User Password. Please refer to page 385 in 41113548_ALEOS 4.13.0 Software Configuration User Guide for AirLink LX60_r1.pdf for more details.
You can get the document at here: https://source.sierrawireless.com/resources/airlink/software_reference_docs/airlink-lx-series---configuration-guide/#sthash.3IrYp9L7.dpbs