After upgrading firmware via web-ui the device stopped responding and all three LEDs for signal strength continiously blinks. We've tried reset, factory reset and finally downgraded and have tested several different versions of firmware. No matter what, all three leds blinks. You can access web-ui on latest version, however the page is entirely blank. If I downgrade one step I get a working web-ui, and after putting the sim-card in slot 2 (if I put it in slot 1, it says no sim) I can't get it to connect. Only says disconnected. No settings for APN anywhere, which is probably the issue here. If I downgrade even further back I get a 500-error when loading the web-ui, saying:
/usr/lib/lua/luci/controller/administration.lua:15: attempt to index field 'hwinfo' (a nil value)
I'm starting to think there's a hardware error with it, but I'm hoping for an easier solution.
The board says TRB255_v3.0.