Cannot add or merge new number to the Caldav account

REPRODUCIBILITY (% or how often): always
BUILD ID = OS VERSION (Settings > About product): 4.0.1.48
HARDWARE (XA2): XA2
UI LANGUAGE: Dutch
REGRESSION: (compared to previous public release: Yes, No, ?): Yes

DESCRIPTION:

Cannot add contact to my active Caldav addressbook. The only option is to add it to the phone itself.

PRECONDITIONS:

Sony Xperia XA2 with a working Caldav account.

STEPS TO REPRODUCE:

  1. Select a phone number frome the phone history
  2. add to a contact
  3. The conact is added to the phone’s memory, cannot change that option.

EXPECTED RESULT: Add the contact to the caldav account, not to the phone’s memory

ACTUAL RESULT: The contact is added to the phone 's memory, cannot choose the Caldav account to save the contact to .

ADDITIONAL INFORMATION:

(Please ALWAYS attach relevant data such as logs, screenshots, etc…)