Validate input inside embedded lists using #DecimalMin and #Valid - spring-boot

Question

So what I am trying to do is to create embedded classes with validation in each class and then get the desired error message when I enter an illegal value. When I have embedded classes, validation suddenly stops working for some reason. I have extracted the core of the problem in the classes below
UserController Class:
// UserController.java
package com.example.demo;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import javax.validation.Valid;
import java.util.ArrayList;
import java.util.List;
#RestController
public class UserController {
public void printUsers(#Valid List<User> users) {
System.out.println(users.get(0).getPeople().get(0).getAge());
}
#GetMapping("/")
public void getUser() {
List<User> users = new ArrayList<>();
Person person = new Person();
person.setAge(-10.0);
person.setFirstName("Test");
person.setLastName("Embedded Validation");
List<Person> persons = new ArrayList<>();
persons.add(person);
User user = new User(persons);
users.add(user);
printUsers(users);
}
}
User Class:
// User.java
package com.example.demo;
import lombok.Builder;
import lombok.Data;
import javax.validation.constraints.NotNull;
import java.util.List;
#Data
#Builder
public class User {
#NotNull
private List<Person> people;
}
Person Class:
// Person.java
package com.example.demo;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;
import javax.validation.constraints.DecimalMin;
import javax.validation.constraints.NotNull;
#Data
#Builder
#AllArgsConstructor
#NoArgsConstructor
public class Person {
#NotNull
#DecimalMin("0.0")
private double age;
#NotNull
private String firstName;
#NotNull
private String lastName;
}
If you run this it will print -10.0, but I have explicitly told the Person class to have a min DecimalVal of 0.0, so my assignment of person.setAge(-10.0); in the UserController class should not be allowed.
How come validation on embedded classes do not work?