When a Spectrum model is placed into Maintenance Mode using a maintenance Schedule, the User that configured the Maintenance Schedule is not shown in the event when the model is placed into Maintenance Mode.
The Spectrum User model for the user that initially created the Maintenance Schedule has been deleted.
The following steps will resolve the issue
1. Log in to OneClick as a user that has read/write access to the model
2. Find and select the local model.
3. Click the Information tab in the Component Detail panel.
4. Expand the General Information subview.
5. Click on the Schedule button.
6. Move the schedule from the Current Schedules column to the Available Schedules column and then click OK.
7. Click on the Schedule button again and this time, move the schedule from the available Schedules column to the Current Schedules column then click OK