[KMail, Kontact] List of activites is incomplete (flatpak)

Hello, i want to use my Plasma activities

in KMail (Kontact), so i have activate the option in the settings

But when i want to select an activity for an identity, there is only one activity without a name

Do I need any additional Flatpak permissions?

Kontact: Version 6.6.3 (25.12.3)

Operating System: Arch Linux
KDE Plasma Version: 6.6.5
KDE Frameworks Version: 6.26.0
Qt Version: 6.11.1
Kernel Version: 7.0.10-arch1-1 (64-bit)
Graphics Platform: Wayland