Cloudflare DynDNS only updating one domain

Hi,

I am using the ddclient plugin to update my cloudflare ddns. Using the folling settings:

Enabled: yes
Service: Cloudflare
Username: token
Password: <API token>
Zone: domain.de
Hostnames: sub1.domain.de sub2.domain.de
Check IP Method: Interface v4
Interface: WAN
Timeout: 10
SSL: yes
Backend: native

API token settings: Zone Zone Read, Zone DNS Edit, specific zone domain.de
Manually set an A record with a random ip for both subdomains.

Logs of opnsense:
Account xxx [cloudflare - ] not modified
Account xxx [cloudflare - ] executing
SUCCESS: sub2.domain.de: skipped: IPv4 address was already set to <my public ipv4> (this one didn't work)
SUCCESS: sub1.domain.de: skipped: IPv4 address was already set to <my public ipv4> (this one did)

Problem is, that only my sub1 getting updatet but not sub2.
I played with the settings backend, username (no username), reboot but no difference.

Anyone any help?