diff --git a/javaxval/src/main/java/org/baeldung/javaxval/methodvalidation/model/Customer.java b/javaxval/src/main/java/org/baeldung/javaxval/methodvalidation/model/Customer.java
index 529cf436da..fe9ad7080e 100644
--- a/javaxval/src/main/java/org/baeldung/javaxval/methodvalidation/model/Customer.java
+++ b/javaxval/src/main/java/org/baeldung/javaxval/methodvalidation/model/Customer.java
@@ -14,7 +14,7 @@ public class Customer {
     @Size(min = 5, max = 200)
     private String lastName;
 
-    public Customer(@Size(min = 5, max = 200) @NotNull String firstName, @Size(min = 5, max = 200) String lastName) {
+    public Customer(@Size(min = 5, max = 200) @NotNull String firstName, @Size(min = 5, max = 200) @NotNull String lastName) {
         this.firstName = firstName;
         this.lastName = lastName;
     }