diff --git a/WebApp/Components/Features/Events/Components/EventAttributes.razor b/WebApp/Components/Features/Events/Components/EventAttributes.razor
index c2ff455..65eaa62 100644
--- a/WebApp/Components/Features/Events/Components/EventAttributes.razor
+++ b/WebApp/Components/Features/Events/Components/EventAttributes.razor
@@ -1,5 +1,9 @@
-@using WebApp.Models
+@using WebApp.Models
 
+@if (EventDefinition is null)
+{
+    return;
+}
 @* @if (EventDefinition.LevelOfEffort.HasValue)
 {
     <span class="numberCircle">@EventDefinition.LevelOfEffort</span>
@@ -27,12 +31,17 @@
 
 @code {
     [Parameter]
-    public required EventDefinition EventDefinition { get; set; }
+    public EventDefinition? EventDefinition { get; set; }
 
     private string _attributes = string.Empty;
 
     protected override void OnParametersSet()
     {
+        if (EventDefinition is null)
+        {
+            _attributes = string.Empty;
+            return;
+        }
         _attributes = EventDefinition.EventFormat == EventFormat.Individual ? AppIcons.IndividualEvent : " ";
         _attributes += EventDefinition.OnSiteActivity ? AppIcons.OnSiteActivity : " ";
         _attributes += EventDefinition.RegionalEvent ? AppIcons.RegionalEvent : " ";
diff --git a/WebApp/Components/Features/Events/Edit.razor b/WebApp/Components/Features/Events/Edit.razor
index 63c5a93..a2303fd 100644
--- a/WebApp/Components/Features/Events/Edit.razor
+++ b/WebApp/Components/Features/Events/Edit.razor
@@ -1,4 +1,4 @@
-@page "/events/edit"
+@page "/events/edit"
 @attribute [Authorize]
 @using Microsoft.EntityFrameworkCore
 @using WebApp.Components.Shared.Components
@@ -163,9 +163,10 @@
     {
         try
         {
-            // Get the tracked entity from the database
+            // Get the tracked entity from the database (do not Include RelatedCareers:
+            // the same context may already be tracking those Career instances from the initial load,
+            // which would cause "another instance with the same key value is already being tracked").
             var trackedEntity = await context.Events
-                .Include(e => e.RelatedCareers)
                 .FirstOrDefaultAsync(e => e.Id == EventDefinition!.Id);
 
             if (trackedEntity == null)
@@ -177,6 +178,8 @@
 
             // Update scalar properties from the form-bound entity
             context.Entry(trackedEntity).CurrentValues.SetValues(EventDefinition!);
+            // RelatedCareersText is not mapped; copy it so ProcessRelatedCareersAsync can use it
+            trackedEntity.RelatedCareersText = EventDefinition!.RelatedCareersText;
 
             // Normalize and process related careers
             await EventDefinitionService.ProcessRelatedCareersAsync(trackedEntity);
diff --git a/WebApp/Components/Features/Teams/Printout.razor b/WebApp/Components/Features/Teams/Printout.razor
index 7c4c84d..3aa9310 100644
--- a/WebApp/Components/Features/Teams/Printout.razor
+++ b/WebApp/Components/Features/Teams/Printout.razor
@@ -244,6 +244,8 @@ else
                 .AsNoTracking()
                 .Include(e => e.Teams)
                 .ThenInclude(e => e.Captain)
+                .Include(e => e.Teams)
+                .ThenInclude(e => e.Event)
                 .Include(e => e.EventRankings)
                 .ThenInclude(e => e.EventDefinition)
                 .OrderBy(e => e.FirstName).ToArrayAsync();
diff --git a/WebApp/Services/EventDefinitionService.cs b/WebApp/Services/EventDefinitionService.cs
index da63e6a..8ba4d5e 100644
--- a/WebApp/Services/EventDefinitionService.cs
+++ b/WebApp/Services/EventDefinitionService.cs
@@ -38,9 +38,11 @@ public class EventDefinitionService
             return;
         }
 
-        // Get all existing careers from database (case-insensitive lookup)
+        // Get existing careers with tracking so we use the same instances the context
+        // may already be tracking (e.g. from the event's RelatedCareers). Using
+        // AsNoTracking() would create duplicate instances and cause "another instance
+        // with the same key value is already being tracked".
         var existingCareers = await _context.Careers
-            .AsNoTracking()
             .Where(c => !string.IsNullOrWhiteSpace(c.Name))
             .ToListAsync();