diff --git a/catalog/dto/product.go b/catalog/dto/product.go
index 8c21800..70ce275 100644
--- a/catalog/dto/product.go
+++ b/catalog/dto/product.go
@@ -9,12 +9,12 @@ type GetProductRequestDTO struct {
 }
 
 type GetProductResponseDTO struct {
-	ID        string    `json:"id"`
-	Name      string    `json:"name"`
-	Slug      string    `json:"slug"`
-	Price     float64   `json:"price"`
-	CreatedAt time.Time `json:"created_at"`
-	UpdatedAt time.Time `json:"updated_at,omitempty"`
+	ID        string     `json:"id"`
+	Name      string     `json:"name"`
+	Slug      string     `json:"slug"`
+	Price     float64    `json:"price"`
+	CreatedAt time.Time  `json:"created_at"`
+	UpdatedAt *time.Time `json:"updated_at,omitempty"`
 }
 
 type GetProductListRequestDTO struct {
diff --git a/catalog/entity/product.go b/catalog/entity/product.go
index 4aa7cd6..fc3f40d 100644
--- a/catalog/entity/product.go
+++ b/catalog/entity/product.go
@@ -3,10 +3,10 @@ package catalog
 import "time"
 
 type Product struct {
-	ID        string    `json:"id", db:"id"`
-	Slug      string    `json:"slug", db:"slug"`
-	Name      string    `json:"name", db:"name"`
-	Price     float64   `json:"price", db:"price"`
-	CreatedAt time.Time `json:"created_at", db:"created_at"`
-	UpdatedAt time.Time `json:"updated_at", db:"updated_at, omitempty"`
+	ID        string     `json:"id", db:"id"`
+	Slug      string     `json:"slug", db:"slug"`
+	Name      string     `json:"name", db:"name"`
+	Price     float64    `json:"price", db:"price"`
+	CreatedAt time.Time  `json:"created_at", db:"created_at"`
+	UpdatedAt *time.Time `json:"updated_at", db:"updated_at, omitempty"`
 }
diff --git a/catalog/model/product.go b/catalog/model/product.go
index 72096eb..bd6ddc0 100644
--- a/catalog/model/product.go
+++ b/catalog/model/product.go
@@ -5,9 +5,9 @@ import (
 )
 
 type Product struct {
-	Name      string    `db:"name"`
-	Slug      string    `db:"slug"`
-	Price     float64   `db:"price"`
-	CreatedAt time.Time `db:"created_at"`
-	UpdatedAt time.Time `db:"updated_at,omitempty"`
+	Name      string     `db:"name"`
+	Slug      string     `db:"slug"`
+	Price     float64    `db:"price"`
+	CreatedAt time.Time  `db:"created_at"`
+	UpdatedAt *time.Time `db:"updated_at,omitempty"`
 }