No connection between Sensor Hub - 4G Data Logger and computer

Hi,

Some time ago I installed sense cap weather station and connected it to Sensor Hub - 4G Data Logger. Whole system worked well for about one month but recently data were not transfered to server so I decidec to checked for reason. Initially I replaced sim and ensures that sims are ok. This did not help. After, I decided to connect to the Hub and check its configuration. I frist used mac and attached to the hub USB-TLL cable but I could not connect to the hub. After I used also PC but I could not connect to the hub also. Hub is powered since each time i turn it on, LED on power button emmiting red light.Can you help with that?