Subscription Calendar Events are not returned by REPORT dav request

Steps to reproduce

1. Add a new calender from an ical link
2. the dates does not show anymore

Expected behavior

The dates shpoud show, it workded until approx 2 weeks ago.

Actual behaviour

the dates does not show anymore in the webinterface of nextcloud

Calendar app version

4.6.0

CalDAV-clients used

davx5

Browser

firefox, chromium actual versions

Client operating system

opensuse 15.5

Server operating system

opensuse 15.5

Web server

Apache

Database engine version

MariaDB

PHP engine version

None

Nextcloud version

28.0.0 rc2

Updated from an older installed version or fresh install

Updated from an older version

List of activated apps

No response

Nextcloud configuration

Enabled:
- activity: 2.20.0
- admin_audit: 1.18.0
- calendar: 4.6.0
- circles: 28.0.0-dev
- cloud_federation_api: 1.11.0
- comments: 1.18.0
- contacts: 5.5.0-rc.2
- cookbook: 0.10.4
- dav: 1.29.1
- deck: 1.12.0-beta.4
- federatedfilesharing: 1.18.0
- federation: 1.18.0
- files: 2.0.0
- files_external: 1.20.0
- files_markdown: 2.4.1
- files_mindmap: 0.0.30
- files_pdfviewer: 2.9.0
- files_reminders: 1.1.0
- files_sharing: 1.20.0
- files_trashbin: 1.18.0
- files_versions: 1.21.0
- firstrunwizard: 2.17.0
- forms: 4.0.0-alpha.2
- groupfolders: 16.0.0
- keeweb: 0.6.13
- logreader: 2.13.0
- lookup_server_connector: 1.16.0
- mail: 3.5.0-rc.2
- nextcloud_announcements: 1.17.0
- notes: 4.9.0-beta.3
- notifications: 2.16.0
- oauth2: 1.16.3
- password_policy: 1.18.0
- photos: 2.4.0
- polls: 6.0.0-rc1
- previewgenerator: 5.4.0
- privacy: 1.12.0
- provisioning_api: 1.18.0
- recommendations: 2.0.0
- related_resources: 1.3.0
- richdocuments: 8.3.0-beta.1
- serverinfo: 1.18.0
- settings: 1.10.0
- sharebymail: 1.18.0
- spreed: 18.0.0-rc.2
- support: 1.11.0
- survey_client: 1.16.0
- suspicious_login: 6.0.0
- systemtags: 1.18.0
- tasks: 0.15.0
- text: 3.9.1
- theming: 2.3.0
- twofactor_admin: 4.4.0
- twofactor_backupcodes: 1.17.0
- twofactor_email: 2.7.4
- twofactor_totp: 10.0.0-beta.2
- updatenotification: 1.18.0
- user_status: 1.8.1
- viewer: 2.2.0
- weather_status: 1.8.0
- workflowengine: 2.10.0
Disabled:
- afterlogic: 2.0.8 (installed 2.0.8)
- audioplayer: 3.4.0 (installed 3.4.0)
- bruteforcesettings: 2.8.0
- calendar_resource_management: 0.6.0-alpha.1 (installed 0.6.0-alpha.1)
- contactsinteraction: 1.9.0 (installed 1.2.0)
- customproperties: 2.0.4 (installed 2.0.4)
- dashboard: 7.8.0 (installed 7.6.0)
- drawio: 2.1.4 (installed 2.1.4)
- encryption: 2.16.0
- files_readmemd: 2.0.0 (installed 2.0.0)
- files_rightclick: 0.15.1 (installed 1.6.0)
- files_videoplayer: 1.14.0
- integration_collaboard: 1.0.6 (installed 1.0.6)
- phonetrack: 0.7.6 (installed 0.7.6)
- user_ldap: 1.19.0

Web server error log

No response

Log file

No response

Browser log

No response

Additional info

No response

The report provides no source file, test, log, or entry point. Reproduce with a subscribed iCal calendar and a CalDAV REPORT request, then verify that subscription events are returned and dates reappear in the web interface.