Modem dropped in Raspberry Pi3 and I can find it anymore, despite it is visible with lsusb

So, I am facing a problem with several Rpi units I have here. Most of the time they work fine, but after several days, the LTE modem (TELIT 910C1-LA) stops working with no reason. Luckily, I could reproduce the problem and saw what is happening before it: The system has booted I have a HTML page that exhibits the modem status LTE Modem had the status: "Connecting" LTE Modem has changed the status to "Disconnecting" LTE Modem has changed the status to blank I have connected trought SSH to the Rpi and run some commands to check what was happening: mmcli -L has returned "No modems were found" mmcli -m 0 has returned "couldn't find modem at " qmicli -d has returned the ICCID of the SIM Card It seems to me that the modem has dropped, then I have connected SSH again an checked the lsusb: It is possible to see that the "Telit Wireless Solution" is conencted on the USB Do you guys has any tips on that? I am kind of newbie to Linux OS, I know how to execute basic commands, but I am definetly not an advanced user. Thanks in advance! I did not tried anything, as I don't want the problem to go away before further analisys. This is an intermitent problem and I want to understand why it is happening and how can I fix it.