diff --git a/CHANGELOG.md b/CHANGELOG.md
index d0f0b54..af4d42d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,5 @@
 ## [Unreleased]
-+* no unreleased changes
+* fix bootstrap 5 data attribute with BS namespace
 
 ## 2.4.0 / 2025-01-31
 ### Changed
diff --git a/app/helpers/ndr_error/errors_helper.rb b/app/helpers/ndr_error/errors_helper.rb
index 9b28641..2b6a100 100644
--- a/app/helpers/ndr_error/errors_helper.rb
+++ b/app/helpers/ndr_error/errors_helper.rb
@@ -33,10 +33,10 @@ def multiple_occurrences_badge_for(fingerprint)
 
       text = "+ #{fingerprint.count - 1}"
       opts = {
-        'class'          => 'badge badge-info',
-        'data-toggle'    => 'tooltip',
-        'data-placement' => 'right',
-        'title'          => "Since #{fingerprint.created_at.to_formatted_s(:db)}"
+        'class'             => 'badge badge-info',
+        'data-bs-toggle'    => 'tooltip',
+        'data-bs-placement' => 'right',
+        'data-bs-title'     => "Since #{fingerprint.created_at.to_formatted_s(:db)}"
       }
 
       content_tag(:span, text, opts)
diff --git a/app/views/ndr_error/errors/show.html.erb b/app/views/ndr_error/errors/show.html.erb
index 76fbf0b..9d30b85 100644
--- a/app/views/ndr_error/errors/show.html.erb
+++ b/app/views/ndr_error/errors/show.html.erb
@@ -22,7 +22,7 @@
         <%= previous_button_for(@error.previous) %>
 
         <div class="btn-group">
-          <a class="btn btn-outline-secondary dropdown-toggle" data-toggle="dropdown" href="#">
+          <a class="btn btn-outline-secondary dropdown-toggle" data-bs-toggle="dropdown" href="#">
             <%= pluralize(@error.similar_errors.length - 1, 'Similar Error') %> Stored
             <span class="caret"></span>
           </a>
@@ -45,7 +45,7 @@
 
     <% if @fingerprint.caused_error_fingerprints.any? %>
       <div class="btn-group">
-        <a class="btn btn-outline-secondary dropdown-toggle" data-toggle="dropdown" href="#">
+        <a class="btn btn-outline-secondary dropdown-toggle" data-bs-toggle="dropdown" href="#">
           <%= pluralize(@fingerprint.caused_error_fingerprints.length, 'Downstream Error') %> Stored
           <span class="caret"></span>
         </a>
diff --git a/test/unit/helpers/ndr_error/errors_helper_test.rb b/test/unit/helpers/ndr_error/errors_helper_test.rb
index 1bf86b6..664abd1 100644
--- a/test/unit/helpers/ndr_error/errors_helper_test.rb
+++ b/test/unit/helpers/ndr_error/errors_helper_test.rb
@@ -56,8 +56,8 @@ class ErrorsHelperTest < ActionView::TestCase
       print.stubs(count: 3)
 
       actual   = multiple_occurrences_badge_for(print)
-      expected = '<span class="badge badge-info" data-placement="right"' \
-                 ' data-toggle="tooltip" title="Since 2015-01-01">+ 2</span>'
+      expected = '<span class="badge badge-info" data-bs-placement="right"' \
+                 ' data-bs-toggle="tooltip" data-bs-title="Since 2015-01-01">+ 2</span>'
 
       assert_dom_equal expected, actual
     end