sssd wont cache passwords although cache_credentials is set

Question

I have a Host, which is able to use my AD to authenticate the users.

But when I use a vpn to a customer system, the connection to the AD is no longer available, and after some inactivity, the screensaver activates and prompts me for a password.

The problem now is, that my sssd_cache wont let me authenticate on the Host, and I need to restart my Host.

in the /etc/sssd/sssd.conf the option "cache_credentials" is enabled.

its a ubuntu 22.04 LTS

sssd version is 2.6.3

config:

ad_domain = domain.lan
auto_private_groups = True
cache_credentials = True
default_shell = /bin/bash
dyndns_update = False
enumerate = True
fallback_homedir = /home/%u
id_provider = ad
krb5_realm = DOMAIN.LAN
krb5_store_password_if_offline = True
ldap_access_order = expire
ldap_account_expire_policy = ad
ldap_force_upper_case_realm = True
ldap_group_gid_number = gidNumber
ldap_group_name = sAMAccountName
ldap_group_object_class = group
ldap_id_mapping = False
ldap_user_fullname = displayName
ldap_user_gecos = displayName
ldap_user_home_directory = unixHomeDirectory
ldap_user_name = sAMAccountName
ldap_user_object_class = user
ldap_user_principal = userPrincipalName
ldap_user_shell = loginShell
override_homedir = /home/%u
realmd_tags = manages-system joined-with-adcli
use_fully_qualified_names = False

there is no "cachedPassword" attribute in the ldb file

Any ideas why my sssd dont cache the passwords?

connect via vpn to a customer system, use the screensaver function, login again with the cached Password from sssd