use lineinfile

roles/awstats/tasks/enable.yml

@@ -10,7 +10,7 @@
     path: /etc/apache2/sites-enabled/awstats.conf
     state: absent
   when: not awstats_enabled and is_debuntu
-  
+
 - name: Restart Apache service ({{ apache_service }})
   systemd:
     name: "{{ apache_service }}"

roles/awstats/tasks/install.yml

@@ -95,6 +95,8 @@
   when: awstats_enabled and is_debuntu
 
 - name: Add 'awstats_installed' variable values to {{ iiab_installed }}
-  ini_file:
-    path: "{{ iiab_installed }}"
-    value: awstats_installed
+  lineinfile:
+    dest: "{{ iiab_installed }}"
+    regexp: '^awstats_installed'
+    line: 'awstats_installed'
+    state: present