diff --git a/CHANGES.md b/CHANGES.md
index 3d33336788..512df9b889 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,4 +1,5 @@
 # 6.5.12 2024-??-??
+ - 2025-01-21 Fixed Bug - Problem when handling errors in the owner field in the activity dialog. Thanks to Daylton Rodrigues (@dayltonr) for reporting. [#627](https://github.com/znuny/Znuny/issues/627).
  - 2025-01-16 Increased size of columns profile_key and profile_value of database table search_profile.
  - 2024-12-23 Improved ACL checks in ticket overview modules.
  - 2024-12-17 Fixed time zone handling for cron events.
diff --git a/Kernel/Modules/AgentTicketProcess.pm b/Kernel/Modules/AgentTicketProcess.pm
index 526905eeff..5948982fec 100644
--- a/Kernel/Modules/AgentTicketProcess.pm
+++ b/Kernel/Modules/AgentTicketProcess.pm
@@ -3564,7 +3564,7 @@ sub _RenderOwner {
 
     # set server errors
     my $ServerError = '';
-    if ( IsHashRefWithData( $Param{Error} ) && $Param{Error}->{'Owner'} ) {
+    if ( IsHashRefWithData( $Param{Error} ) && $Param{Error}->{'OwnerID'} ) {
         $ServerError = 'ServerError';
     }