I installed a second Nextcloud Instance on a proxmox-server. With this instance I got the problem that I cannot sync my Contacts from my Android phone, but Calendar works.
I can add new adressbooks on my phone with OpenSync and I can see them in my nextcloud, but it doesn’t sync my contacts. I can add new contacts in NC, and they’re added in my phone. But my Contacts on my Phone are not send to my NC.
nothing. Just installed a new NC. But I found the issue. Out of the sudden I need to copy my contacts to the OpenSync/DavDroid contactbook with a copy app or something like that. Then it works. I didn’t do that before. Strange.