Just wanted to share this little bit of info here.
If you’re like me, working on an iPhone - having multiple contact-accounts connected. You’ll notice that you can not select a default account if you have miab cardDav sync setup. It will plainly not give you an option to select a default account or your default account will automatically be something else other than your miab cardDav.
After some digging I found this.
I remember this edit from my own nextcloud config some years ago.
So head over to
/usr/local/lib/owncloud/
and run the following command to check the enabled apps
sudo -u www-data php occ app:list
so you can see the contacts interaction app is enabled.
now run
sudo -u www-data php occ app:disable contactsinteraction
Et voila - disable and enable the cardDav account on your iphone. Lo and behold, the option to select a default account on your iPhone is available again. Gone are the days of wrongly synced contacts. Not sure if it stays disabled when upgraded, will report back if it does. In the meantime, rejoice!
edit to include nextcloud’s documentation over here.