trying to mark task as completed returns error http 200

[Aaaamu]

Describe the bug
trying to mark any task on caldav list as completed opens a notice at the bottom of the window returns error http 200 (see below). the task remains unchanged.

To Reproduce
Steps to reproduce the behavior:
go to any caldav list and try to mark a task as completed

Expected behavior
a change in the state of the task and no error

Desktop (please complete the following information):
client:
Betriebssystem: Kubuntu 22.04
KDE-Plasma-Version: 5.24.7
KDE-Frameworks-Version: 5.92.0
Qt-Version: 5.15.3
Kernel-Version: 5.15.0-92-generic (64-bit)
Grafik-Plattform: X11

Server:
Yunohost server (debian based)
Nextcloud Hub 8 (29.0.5)

Additional context
This seems to be a mismatch of what the server expects and what planify expects. Maybe some error in the authentication? notice that the refreshing symbol constantly spins next to the account name of the caldav account in planify. Something that comes to mind is, that planify wants the url of the nextcloud installation only when setting the accounts up, while most software would want the exact url to the caldav api. maybe there is an inconsequent completion of the nextcloud caldav url in some part of the code?

The error returned:
HTML 200
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