[Bug]: Icloud mail adress wont work

⚠️ This issue respects the following points: ⚠️

[X] This is a bug, not a question or a configuration/webserver/proxy issue.
[X] This issue is not already reported on Github (I've searched it).
[X] Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
[X] Nextcloud Server is running on 64bit capable CPU, PHP and OS.
[X] I agree to follow Nextcloud's Code of Conduct.

Bug description

My iCloud mail address does not sync with Nextcloud. I’m getting the following error: No messages in this mailbox. However, my other mail addresses work on Nextcloud Mail and my iCloud Mail-adress works on other Mail apps(such as Windows Mail, outlook, ...). I checked the IMAP and SMPT settings and they are right. When I get a new E-Mail, it shows a one next to the Mailbox but won't load the mail. So it’s only my iCloud Mail address that won't sync with Nextcloud but does with other Programs

Steps to reproduce

1.Add a Icloud Mail adress 2. 3.

Expected behavior

Sync the Mailbox

Installation method

Official All-in-One appliance

Nextcloud Server version

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.1

Web server

Apache (supported)

Database engine version

MySQL

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

Fresh Nextcloud Server install

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

What user-backends are you using?

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

Configuration report

"system": {
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "192.168.11.5",
            "famhennig.eu",
            "www.famhennig.eu"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "mysql",
        "version": "26.0.1.1",
        "overwrite.cli.url": "http:\/\/192.168.11.5",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "maintenance": false,
        "mail_smtpmode": "smtp",
        "mail_sendmailmode": "smtp",
        "mail_smtpport": "587",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpauth": 1,
        "mail_smtpauthtype": "LOGIN",
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "default_phone_region": "DE",
        "memcache.local": "\\OC\\Memcache\\APCu",
        "theme": "",
        "loglevel": 2,
        "app_install_overwrite": [
            "occweb"
        ],
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "twofactor_enforced": "true",
        "twofactor_enforced_groups": [
            "admin",
            "Freunde"
        ],
        "twofactor_enforced_excluded_groups": [
            "Familie"
        ],
        "remember_login_cookie_lifetime": 1296000,
        "session_lifetime": 3600,
        "session_keepalive": false,
        "auto_logout": true,
        "opcache.save_comments": 1
    }
}

List of activated Apps

Enabled:
  - activity: 2.18.0
  - admin_audit: 1.16.0
  - bruteforcesettings: 2.6.0
  - cfg_share_links: 3.0.2
  - circles: 26.0.0
  - cloud_federation_api: 1.9.0
  - comments: 1.16.0
  - contacts: 5.2.0
  - contactsinteraction: 1.7.0
  - dashboard: 7.6.0
  - dav: 1.25.0
  - deck: 1.9.2
  - federatedfilesharing: 1.16.0
  - federation: 1.16.0
  - files: 1.21.1
  - files_antivirus: 5.0.0
  - files_pdfviewer: 2.7.0
  - files_rightclick: 1.5.0
  - files_sharing: 1.18.0
  - files_trashbin: 1.16.0
  - files_versions: 1.19.1
  - firstrunwizard: 2.15.0
  - logreader: 2.11.0
  - lookup_server_connector: 1.14.0
  - mail: 3.1.1
  - nextcloud_announcements: 1.15.0
  - notes: 4.7.2
  - notifications: 2.14.0
  - oauth2: 1.14.0
  - password_policy: 1.16.0
  - passwords: 2023.5.30
  - photos: 2.2.0
  - privacy: 1.10.0
  - provisioning_api: 1.16.0
  - recommendations: 1.5.0
  - related_resources: 1.1.0-alpha1
  - richdocuments: 8.0.2
  - richdocumentscode: 22.5.1301
  - serverinfo: 1.16.0
  - settings: 1.8.0
  - sharebymail: 1.16.0
  - spreed: 16.0.3
  - support: 1.9.0
  - survey_client: 1.14.0
  - suspicious_login: 4.4.0
  - systemtags: 1.16.0
  - tasks: 0.15.0
  - text: 3.7.2
  - theming: 2.1.1
  - twofactor_backupcodes: 1.15.0
  - twofactor_totp: 8.0.0-alpha.0
  - updatenotification: 1.16.0
  - user_status: 1.6.0
  - viewer: 1.10.0
  - weather_status: 1.6.0
  - workflowengine: 2.8.0
Disabled:
  - encryption: 2.14.0
  - files_external: 1.18.0
  - user_ldap: 1.16.0

Nextcloud Signing status

No errors have been found.

Nextcloud Logs

{"reqId":"JCrA0LBApMcWI19QKSTF","level":2,"time":"2023-03-09T14:22:07+00:00","remoteAddr":"*.*.*.*","user":"--","app":"no app in context","method":"GET","url":"/",>

Additional info

readding the mail adress has been tried

nextcloud / mail