CardDav sync to dav.mi.com failed with error 500

[xuziq2000]

I have a device of Mi5s, runnint AOKP rom Mokee(https://mokeedev.com) which provides no XiaoMiAccount. As a result, I’ve installed DAVx5 to get my contacts back from server.
It works well on syncing data from SERVER to DEVICE, but when I make any change on my device, sync DO raise errors of “Internal error 500”.

Here is the log:
https://paste.fedoraproject.org/paste/l08pDIOeiOjzRO7pZY8Pww

[rfc2822]

Hello,

The server responds with “Internal [server] error 500”, and the request seems to be OK. What does your server support say about this?

PS: What is dav.mi.com? Are there test accounts?

[xuziq2000]

Hello,
dav.mi.com is carddav server of miui.com(also known as xiaomi.com).
I’m sorry for taking no test account. I’ve only got my own.

By the way,I’ve found that miui.com authorize user by OAuth2. Is this anything make sense?

[rfc2822]

@xuziq2000 I see… Seems like it also works without OAuth2, because DAVx⁵ doesn’t support OAuth.

However your problem seems to be a server problem. Is there is anything specific we can do for you, just let us know.