Failed to load documents after update from 14.0.3 to 15.0.12

after updating our Nextcloud from version 14.0.3 to 15.0.12, our collabora integration stopped working. Whenever I am trying to open a document I get the message that the document could not be loaded from disk.

We are using CODE + nginx as docker-containers. This is the Log output when trying to access a document:

This is our nginx config:

We are using the newest versions of CODE ( and nextcloud/richdocuments (3.4.3).

I hope that someone has an idea how to fix this.

Best regards,