Can't make any calls

REPRODUCIBILITY (% or how often): 100%
BUILD ID = OS VERSION (Settings > About product): 4.2.0.21
HARDWARE (XA2, X10, X10 II, …): X10 II
UI LANGUAGE: English
REGRESSION: (compared to previous public release: Yes, No, ?): Yes

DESCRIPTION:

I can receive calls but cannot dial any numbers…

PRECONDITIONS:

Swiss SIM (Salt) + fresh SFOS 4.2 on X 10 II

STEPS TO REPRODUCE:

  1. open dialler
  2. type a number or select a contact
  3. app will freeze for a second but won’t start a call

EXPECTED RESULT:

Call is started

ACTUAL RESULT:

No call is started

ADDITIONAL INFORMATION:

From the log: seems that some setting is missing?

Sep 20 09:37:33 Xperia10II-DualSIM voicecall-ui[6376]: [W] unknown:0 - QString VoiceCallManager::defaultProviderId() const No provider added
Sep 20 09:37:33 Xperia10II-DualSIM voicecall-ui[6376]: [W] unknown:332 - file:///usr/share/voicecall-ui-jolla/VoiceCallManager.qml:332:5: QML VoiceCallManager: No provider found for modemPath: /ril_0