diff --git a/subiquity/models/subiquity.py b/subiquity/models/subiquity.py
index 43814794..90429063 100644
--- a/subiquity/models/subiquity.py
+++ b/subiquity/models/subiquity.py
@@ -171,7 +171,7 @@ class SubiquityModel:
                 'passwd': user.password,
                 'shell': '/bin/bash',
                 'groups': groups,
-                'lock-passwd': False,
+                'lock_passwd': False,
                 }
             if self.ssh.authorized_keys:
                 user_info['ssh_authorized_keys'] = self.ssh.authorized_keys