fix: lms quiz type error (#21152)

diff --git a/erpnext/public/js/education/lms/quiz.js b/erpnext/public/js/education/lms/quiz.js
index 5248129..91cbbf4 100644
--- a/erpnext/public/js/education/lms/quiz.js
+++ b/erpnext/public/js/education/lms/quiz.js
@@ -29,7 +29,7 @@
 			this.questions.push(question)
 			this.wrapper.appendChild(question_wrapper);
 		})
-		if (data.activity.is_complete) {
+		if (data.activity && data.activity.is_complete) {
 			this.disable()
 			let indicator = 'red'
 			let message = 'Your are not allowed to attempt the quiz again.'
diff --git a/erpnext/www/lms/content.html b/erpnext/www/lms/content.html
index 5607c08..cdc7141 100644
--- a/erpnext/www/lms/content.html
+++ b/erpnext/www/lms/content.html
@@ -63,7 +63,7 @@
 		</a>
 	</div>
 	<div>
-		<h1>{{ content.name }} <span class="small text-muted">({{ position + 1 }}/{{length}})</span></h1>
+		<h2>{{ content.name }} <span class="small text-muted">({{ position + 1 }}/{{length}})</span></h2>
 	</div>
 {% endmacro %}