diff --git a/tasks/backup_volume.yml b/tasks/backup_volume.yml
index 7cb4ae7..ab2b0f7 100755
--- a/tasks/backup_volume.yml
+++ b/tasks/backup_volume.yml
@@ -7,7 +7,7 @@
 - name: Assert that there is no hard links in /mnt/volumes/{{ item }}
   ansible.builtin.assert:
     that:
-      - find_hard_links.stdout | length = 0
+      - find_hard_links.stdout | length == 0
     msg: "Duplicity does not support hard links."
 
 - name: Backup with duplicity