MAX 700 no longer tethering to 7730L


Hello all,
After more than a year of trouble-free USB tethering of my Mifi7730L Verizon hotspot. It has quit tethering sometime during the last week or so. It charges, but the MAX700 doesn’t recognize it on the dashboard. I changed the USB port and cable, no change. I updated the MAX700 to the latest posted firmware in an attempt to rectify the problem, with no change. Any notion as to what happened? My 7730L firmware hasn’t updated in some time…