diff --git a/tasks/main.yml b/tasks/main.yml
index 09b8d4c..bf20e2b 100644
--- a/tasks/main.yml
+++ b/tasks/main.yml
@@ -95,7 +95,7 @@
 
 - name: Configurar lookup tables
   include_tasks: lookup_tables.yml
-  loop: "{{ postfix_mail_domains.keys() }}"
+  loop: "{{ postfix_mail_domains.keys()|list }}"
   loop_control:
     loop_var: domain