Finally I took the leap into the unknown!
Inserted the new sim I got and voila……
Notice the bars and the orange smudge on top.
No idea what this means? I succeeded to make a couple of calls, no issues. But cannot receive calls.
There is no sound and the call is redirected to the voicemail. That part works.
Thank you, anybody?
This mean that Mobile-Data is disabled.
Probably need change 4G only to 4G + 3G only
And right you are! Smudge is gone and the phone vibrates, no sound?
How do I set the sound??
Thank you kindly Carlos.
There are 3 options on the top-slide-down-menu, just hit 1 or 2 or 3 times the Bell icon on slide down menu to change options.
I did not know that! Thank you Carlos. 
Just be careful because sometimes the smudge randomly comes back when I reset the modem with the kill switch. If that happens I found that turning off the mobile data in settings and turning it back on will fix it.
Thank you for the tip 
Got it! 
, Thank you.
