Why am I getting the error messag the cellular phone line is not available. choose a different phone line and try your call again?

I have updated the software yesterday and after I've done this my phone does not want dail out and cannot receive any calls. When I try to phone out the following message appear: the csllular phone line is not available. Choose a different phone line.

Sounds like a botched update. I recommend backing up the device, reloading the system default OS using Link or Blend or whatever your desktop client is. Do not restore data at first, test the device, then restore if needed.

Then yes, call the carrier for additional support if needed.