diff --git a/app/commands.py b/app/commands.py
index 87860a360ed8d1c5006d16c95f771c1f95e54d8f..1075ba19ae9419f7fe1435bf8aef28bf9f98302e 100644
--- a/app/commands.py
+++ b/app/commands.py
@@ -54,7 +54,9 @@ def sync_user(connection, user):
             disable_user(user)
         else:
             attributes = ldap_user["attributes"]
-            user.display_name = utils.attribute_to_string(attributes["cn"])
+            user.display_name = (
+                utils.attribute_to_string(attributes["cn"]) or user.username
+            )
             user.email = utils.attribute_to_string(attributes["mail"])
             groups = ldap_manager.get_user_groups(
                 dn=ldap3.utils.conv.escape_filter_chars(ldap_user["dn"]),