Nextcloud & z-push synchronizing pictures between nextcloud and Android/outlook


I have setup a server running Nextcloud, which I am using as email, calendar and contact frontend (and of course for file synchronization) and z-push to sync to Outlook or my Android devices. It works almost perfectly.

The only thing that I cannot get to work :rage: is the synchronization of contact photos. I found the setting in z-push to sync pictures of up to 5MB and I kept that standard. 5MB is plenty and should absolutely suffice for my purposes. But when I add a photo to a contact in Nextcloud or on my Android devices they are not synced. I am sure I have to change some settings I just could not find them, neither in Nextcloud nor in z-push.
Can anybody point me in the right direction? That would be fantastic.

Thanks in advance.