diff --git a/roles/zammad/tasks/ssl.yml b/roles/zammad/tasks/ssl.yml
index 6e9913d9..92dfd034 100644
--- a/roles/zammad/tasks/ssl.yml
+++ b/roles/zammad/tasks/ssl.yml
@@ -30,19 +30,19 @@
 - name: "SSL | Check if certificate is still valid, ignoring failures"
   community.crypto.x509_certificate_info:
     path: "{{ zammad_ssl_cert_path }}"
-  register: "certificate"
+  register: "__certificate"
   ignore_errors: "{{ ansible_check_mode }}"
 
 - name: "SSL | Ensure certificate and private key match"
   community.crypto.openssl_privatekey_info:
     path: "{{ zammad_ssl_key_path }}"
-  register: "private_key"
+  register: "__private_key"
   ignore_errors: "{{ ansible_check_mode }}"
 
 - name: "SSL | Validate that certificate is still valid"
   ansible.builtin.assert:
     that:
-      - "not certificate.expired"
-      - "certificate.public_key == private_key.public_key"
+      - "not __certificate.expired"
+      - "__certificate.public_key == __private_key.public_key"
 
 ...