@rfc2822 thank you so much for your support
I am having a very similar problem with my Synology NAS and my Galaxy S5.
I have to say that I did not understand the answer above at all.
I receive “Couldn’t find CalDAV or CardDAV service.” The debug log is attached.
I have the contacts syncing correctly, bu not the contacts. Both work fine on Thunderbird.
What else would you need to offer advice on how to fix this?
Did you have a look at https://www.davdroid.com/tested-with/synology/, including the video?
Yes I did. My NAS is too old for the Calendar package so I use WebDAV. I’ve followed those instructions and still I have the problem. The same URL and credentials work with Thunderbird.
Is CardDAV really handled by the WebDAV package or by a separate server? As far as I remember, the CardDAV server was always separate.
According to the logs: http://192.168.0.101:5005/homes/Louise/Calendar/ returns 405 Method not allowed, so I wonder how other clients can work with this URL.