To confirm whether this is the case, follow the steps below.
  1. Fundraising > select TeamRaiser
  2. Find the TeamRaiser and click Manage
  3. Select Event Managers
  4. Find the event manager and click Edit this contact
  5. Under the contact information, notice how it says (Removed)
The solution is to create a new constituent record for this person or reactivate them. If you had to recreate the constituent record, then you will need to assign them as an Event Manager again.