1st without errors

src/main/java/com/example/nto/entity/Employee.java

@@ -1,5 +1,7 @@
 package com.example.nto.entity;
 
+import com.fasterxml.jackson.annotation.JsonManagedReference;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
 import jakarta.persistence.*;
 import lombok.AllArgsConstructor;
 import lombok.Builder;
@@ -20,6 +22,7 @@ import java.util.List;
 @NoArgsConstructor
 @AllArgsConstructor
 @Entity
+@JsonSerialize
 public class Employee {
 
     @Id
@@ -32,7 +35,9 @@ public class Employee {
 
     private String photoUrl;
 
-    @OneToMany(mappedBy = "employee", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
+    @OneToMany(mappedBy = "employee", cascade = CascadeType.ALL, fetch = FetchType.LAZY,
+            targetEntity = Booking.class)
+    @JsonManagedReference
     private List<Booking> bookingList;
 
     public Employee(long id, String name, String code, String photoUrl) {