diff --git a/app/assets/javascripts/utils/api.js b/app/assets/javascripts/utils/api.js
index a18b92d946..6e596df7be 100644
--- a/app/assets/javascripts/utils/api.js
+++ b/app/assets/javascripts/utils/api.js
@@ -321,23 +321,22 @@ const API = {
     });
 
     if (!response.ok) {
-      if (response.status === 422 ) {
-      const data = await response.json();
-      const errorMessage = data.errors?.[0] || 'Unknown error';
-      throw new Error(errorMessage);}
-      else {
       const data = await response.text();
       this.obj = data;
       this.status = response.statusText;
       SentryLogger.obj = this.obj;
       SentryLogger.status = this.status;
-      Sentry.captureMessage('saveCourse failed', {
-        level: 'error',
-        extra: SentryLogger
-      });
+      try {
+        Sentry.captureMessage('saveCourse failed', {
+          level: 'error',
+          extra: SentryLogger
+        });
+      } catch (error) {
+        console.error("Sentry.captureMessage failed:", error);
+      };
       response.responseText = data;
       throw response;
-    }}
+    }
     return response.json();
   },
 
diff --git a/app/controllers/courses_controller.rb b/app/controllers/courses_controller.rb
index dcf824f3af..37e465b822 100644
--- a/app/controllers/courses_controller.rb
+++ b/app/controllers/courses_controller.rb
@@ -44,19 +44,17 @@ def update
     validate
     handle_course_announcement(@course.instructors.first)
     slug_from_params if should_set_slug?
-    if @course.update update_params
+    @course.update update_params
     update_courses_wikis
     update_course_wiki_namespaces
     update_flags
     ensure_passcode_set
     UpdateCourseWorker.schedule_edits(course: @course, editing_user: current_user)
     render json: { course: @course }
-  else
-    render json: { errors: @course.errors.full_messages }, status: :unprocessable_entity
-  end
   rescue Course::DuplicateCourseSlugError => e
   message = I18n.t('courses.error.duplicate_slug', slug: e.slug)
-  render json: { errors: [message] }, status: :unprocessable_entity
+  render json: { errors: e, message: },
+           status: :unprocessable_entity
 
   rescue Wiki::InvalidWikiError => e
     message = I18n.t('courses.error.invalid_wiki', domain: e.domain)
diff --git a/app/models/course.rb b/app/models/course.rb
index 70939c1faa..57d62f679f 100644
--- a/app/models/course.rb
+++ b/app/models/course.rb
@@ -607,7 +607,7 @@ class DuplicateCourseSlugError < StandardError
     def initialize(slug, msg = 'Duplicate Slug')
       @msg = msg
       @slug = slug
-      super('#{msg}: #{slug}')
+      super(msg)
     end
 
     attr_reader :slug