diff --git a/lib/custom_wizard/builder.rb b/lib/custom_wizard/builder.rb
index ea8bdc01..30feee98 100644
--- a/lib/custom_wizard/builder.rb
+++ b/lib/custom_wizard/builder.rb
@@ -415,7 +415,7 @@ class CustomWizard::Builder
                 end
               end
             else
-              value = [*value] + tags if key === 'tags'
+              value = [*value] + [*tags] if key === 'tags'
               params[key.to_sym] = value
             end
           end