@kugiigi I have already tried this. Still doesn't work. I think, it must be forwarded from 3g interface to "local". But I don't know how to do this. (i mean local intarface)
@moriarty
Before using apt-update, make sure your device is up to date ( system-settings->update).
apt upgrade work most of the time, but some updates are expected to be installed in recovery only, making the update broken.
In that case, often a re-install from the installer is ok.