Set Preferred Line Number with Contacts on iPhone XS, XS Max and iPhone XR

  1. On main screen, tap (Contacts) Ex. tap “กรมการบิน”
  2. “กรมการบิน” information will appear > below name, default = Primary, that means Default Voice Line is set = Primary
  3. To change it, tap (Edit), at Contacts Edit page, tap (Preferred Line)
  4. At (Preferred Line), set up as desired, there’ll be a mark shown behind then tap (Done)
  5. Some contact is last used that means it’s already set as Last Used. If one of CELLULAR PLAN is removed, when making call system will apply to use existing Cellular plan