Navigate to "ORCHESTRATOR > Monitoring > Alerts" submenu. Select the preferred entity by clicking the [Entity] button on the top right corner. 

In this section, you can see what are the alerts for this customer entity. When device or link operating status matches the defined trigger condition, an alert is created. When an alert is created, it will be emailed to all users within the entity and parent entity users who have access rights to the current entity.

Severity of the alerts are defined as part of the trigger setting. You can use the filtering function to search alerts by keywords.