R11e-LTE6_V027 is know as stable one.
Now we have v028 and v029 is prepared.
You can do upgrade to 028 first.
Next will be How to correctly diagnose & collect LTE logs for support to see what happends when you lost internet.
Those are first steps.
btw, rsrp: -106dBm & sinr: -5dB not give big hopes with good speed, maybe you can move it in better place ?