fix: N1C. Help users look for "out of sync" Instances in a CSG (#422)

* Point to Out of Sync

Co-authored-by: Sylvia Wang <139922338+sylwang@users.noreply.github.com>
Co-authored-by: Alan Dooley <a.dooley@f5.com>

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Co-authored-by: Sylvia Wang <139922338+sylwang@users.noreply.github.com>
Co-authored-by: Alan Dooley <a.dooley@f5.com>

Author: 3 people

content/nginx-one/how-to/config-sync-groups/manage-config-sync-groups.md

@@ -100,6 +100,12 @@ Now that you created a Config Sync Group, you can add instances to that group. A
 
 Any instance that joins the group afterwards inherits that configuration.
 
+{{< note >}} If you see the following [Config Sync Group Status](#config-sync-group-status) message: **Out of Sync**:
+
+ - Review the instance details in NGINX One Console to identify any publication problems.
+ - After you change the configuration of the Config Sync Group, [Publish it](#publish-the-config-sync-group-configuration].
+In that case, review and resolve discrepancies between the Instance and the rest of the Config Sync Group. {{< /note >}}
+
 ### Add an existing instance to a Config Sync Group {#add-an-existing-instance-to-a-config-sync-group}
 
 You can add existing NGINX instances that are already registered with NGINX One to a Config Sync Group.