Nextcloud 15.0.4 , contacts 3.0.3 , running on apache/debian 9
After running perfectly for a long time, suddenly my complete addressbook disappeared.
After importing my contact list to the DAVx account on the android, and syncing, all contacts are back again in the WebUI. But after 24 hours, they disappear again.
I tried to turn off syncing, but get the empty address book the next day.
What can be wrong? Nothing in the log.