cant syncronise with Nextcloud or add Projets/Lists

[LimoSenpai]

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'New Project' on the connected Nextcloud account
2. Click on 'Add Project' after giving it a name
3. See error

Expected behavior
A project being created

Screenshots

Desktop (please complete the following information):

• OS or DE: Nobara Linux
• Version 40

Additional context
It also doesnt sync existing lists right now. The integration is working on several other devicces with Nextcloud so it shouldnt be my server, The error show the IP of my reverse proxy.

<d:error xmlns:d="DAV:" xmlns:s="http://sabredav.org/ns">
<s:exception>Internal Server Error</s:exception>
<s:message>
The server was unable to complete your request. If this happens again, please send the technical details below to the server administrator. More details can be found in the server log. </s:message>
<s:technical-details>
<s:remote-address>192.168.178.4</s:remote-address>
<s:request-id>Z3m5sELZKV-nrtjWUMKUFAAASA8</s:request-id>
</s:technical-details>
</d:error>