Frequent Network Disconnects - VL600

[VL600_Boston]

I am noticing that my connection fails fairly randomly but too often.   The failure can occur from seconds to eight hours after a connection.  Typical disconnect after one hour or so.    This happens in both New York City and Boston.   I am not mobile at these times -  hotel rooms mostly.   If this continues I probably won't maintain my subscription to the 4G service since I can use the WiFi hotspot feature of my smartphone (on another network).