Hi Mitch,
thanks again for your precious support.
Well, there are news: I had an attempt connecting my interface (connected to the panel of TS 480) direct to the router via LAN.
It worked and I enjoyed it for about half an hour. I disconnected the cable and tried again with WIFI. Again, just yellow led, and same errors as reported above. Tried again with the LAN, worked.
Now, after 2 hours, ...LAN didn't work.
....