iOS Carddav sync not possible

I looked through the topic here but couldn’t find a solution.
I simply want to add carddav from nextcloud to as an addressbook for my ios devices but get the alert “carddav account verification failed”

Used the link:

and working with nextcloud 12 latest update.

The changes the troubleshooting page suggests are already in the .htaccess file.

I have the same issue and find no solution or even get an answer here until now !