Hello
Have you set your Styleset to display the Additional Component?
This will be under the Connector - Decoration - Related Entities - Additional Component - Symbols - set a default.
If you have set that and it does not work, you may need to Apply Styles or Update - Border.
If those actions do not resolve the issue, then let's see if other ideas appear. After which I suggest logging an SR on SupportNet.
Regards,
Pat