Hello,
Thank you for the query. If you could, please send me a troubleshoot file via private message when the modem/SIM card isn't functioning. Any problem regarding the loss of modem/SIM not found is known and has already been passed on to our RnD department. The issue is currently being investigated but we'll always appreciate more help and information. As soon as there's any news regarding this issue, we'll make sure to let everyone know!
What's a troubleshoot file and how to download it:
A Troubleshoot file contains a device's event logs, configuration files and other info useful for diagnostics. It can be downloaded from your device's WebUI, Troubleshoot page:
System → Administration → Troubleshoot
Thank you for any assistance and any sort of follow up in advance!
Best regards,
Tomas.