[Bug]: Period until next appointment incorrect

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

Example: Appointment at 4 pm.
It is noon.
Dashboard says: In 3 hours.

See screenshots (German).

Steps to reproduce

1. Create appointment
2. Call up dashboard

Expected behavior

Expected behavior: In 4 hours

Installation method

Other Community project

Nextcloud Server version

28

Operating system

Debian/Ubuntu

PHP engine version

None

Web server

Nginx

Database engine version

None

Is this bug present after an update or on a fresh install?

None

Are you using the Nextcloud Server Encryption module?

None

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

No response

List of activated Apps

No response

Nextcloud Signing status

No response

Nextcloud Logs

No response

Additional info

No response

No files, tests, or entry points are mentioned. Reproduce the issue by creating an appointment and opening the dashboard, then compare the displayed countdown with the expected period described in the issue. Done means the dashboard reports the correct time until the appointment.