diff --git a/webgoat-container/src/main/java/org/owasp/webgoat/users/UserTracker.java b/webgoat-container/src/main/java/org/owasp/webgoat/users/UserTracker.java
index 645b46258..64ca5fb9a 100644
--- a/webgoat-container/src/main/java/org/owasp/webgoat/users/UserTracker.java
+++ b/webgoat-container/src/main/java/org/owasp/webgoat/users/UserTracker.java
@@ -2,6 +2,7 @@
 package org.owasp.webgoat.users;
 
 import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
 import lombok.extern.slf4j.Slf4j;
 import org.owasp.webgoat.lessons.AbstractLesson;
 import org.owasp.webgoat.lessons.Assignment;
@@ -10,6 +11,7 @@ import javax.persistence.*;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import java.util.Set;
 import java.util.stream.Collectors;
 
 
@@ -50,7 +52,7 @@ public class UserTracker {
     @Id
     private String user;
     @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
-    private List<LessonTracker> lessonTrackers = Lists.newArrayList();
+    private Set<LessonTracker> lessonTrackers = Sets.newHashSet();
 
     private UserTracker() {}
 
diff --git a/webgoat-lessons/cross-site-scripting/src/main/java/org/owasp/webgoat/plugin/CrossSiteScriptingLesson5a.java b/webgoat-lessons/cross-site-scripting/src/main/java/org/owasp/webgoat/plugin/CrossSiteScriptingLesson5a.java
index 27bc2b4d5..7f6683f66 100644
--- a/webgoat-lessons/cross-site-scripting/src/main/java/org/owasp/webgoat/plugin/CrossSiteScriptingLesson5a.java
+++ b/webgoat-lessons/cross-site-scripting/src/main/java/org/owasp/webgoat/plugin/CrossSiteScriptingLesson5a.java
@@ -64,7 +64,7 @@ public class CrossSiteScriptingLesson5a extends AssignmentEndpoint {
 		userSessionData.setValue("xss-reflected1-complete",(Object)"false");
 		StringBuffer cart = new StringBuffer();
 		cart.append("Thank you for shopping at WebGoat. <br />You're support is appreciated<hr />");
-		cart.append("<p>We have chaged credit card:" + field1 + "<br />");
+		cart.append("<p>We have charged credit card:" + field1 + "<br />");
 		cart.append(   "                             ------------------- <br />");
 		cart.append(   "                               $" + totalSale);