diff --git a/action_create.go b/action_create.go
index 2781186..36413d8 100644
--- a/action_create.go
+++ b/action_create.go
@@ -7,7 +7,6 @@ import (
 
 	"github.com/Selly-Modules/logger"
 	"github.com/Selly-Modules/mongodb"
-	"go.mongodb.org/mongo-driver/bson"
 )
 
 // CreateOptions ...
@@ -41,15 +40,8 @@ func (s Service) Create(payload CreateOptions) error {
 		return err
 	}
 
-	// Find device id existed or not
-	device := Device{}
-	if err = col.FindOne(ctx, bson.M{"deviceID": deviceData.DeviceID}).Decode(&device); err != nil {
-		logger.Error("devicemngt - findByDeviceID", logger.LogData{
-			"deviceID": deviceData.DeviceID,
-			"err":      err.Error(),
-		})
-	}
-	if !device.ID.IsZero() {
+	// Find deviceID existed or not
+	if s.isDeviceIDExisted(ctx, deviceData.DeviceID) {
 		return errors.New("this device is already existed")
 	}
 
diff --git a/helper.go b/helper.go
index 3c1d026..3441415 100644
--- a/helper.go
+++ b/helper.go
@@ -1,9 +1,12 @@
 package devicemngmt
 
 import (
+	"context"
 	"fmt"
 
+	"github.com/Selly-Modules/logger"
 	ua "github.com/mssola/user_agent"
+	"go.mongodb.org/mongo-driver/bson"
 	"go.mongodb.org/mongo-driver/mongo"
 )
 
@@ -12,6 +15,25 @@ func (s Service) getDeviceCollection() *mongo.Collection {
 	return s.DB.Collection(fmt.Sprintf("%s-%s", s.TablePrefix, tableDevice))
 }
 
+func (s Service) isDeviceIDExisted(ctx context.Context, deviceID string) bool {
+	var (
+		col    = s.getDeviceCollection()
+		device = Device{}
+	)
+
+	if err := col.FindOne(ctx, bson.M{"deviceID": deviceID}).Decode(&device); err != nil {
+		logger.Error("devicemngt - findByDeviceID", logger.LogData{
+			"deviceID": deviceID,
+			"err":      err.Error(),
+		})
+	}
+	if !device.ID.IsZero() {
+		return true
+	}
+
+	return false
+}
+
 func getOSName(userAgent string) string {
 	uaData := ua.New(userAgent)
 	return uaData.OSInfo().Name
diff --git a/model.go b/model.go
index 22a2796..33dce53 100644
--- a/model.go
+++ b/model.go
@@ -9,7 +9,7 @@ import (
 // Device ...
 type Device struct {
 	ID             primitive.ObjectID `bson:"_id" json:"_id"`
-	DeviceID       string             `bson:"deviceID" json:"deviceID"` // unique
+	DeviceID       string             `bson:"deviceID" json:"deviceId"` // unique
 	IP             string             `bson:"ip" json:"ip"`
 	OSName         string             `bson:"osName" json:"osName"`
 	OSVersion      string             `bson:"osVersion" json:"osVersion"`
@@ -17,7 +17,7 @@ type Device struct {
 	Language       string             `bson:"language" json:"language"` // vi, en
 	IsMobile       bool               `bson:"isMobile" json:"isMobile"`
 	LastActivityAt time.Time          `bson:"lastActivityAt" json:"lastActivityAt"`
-	UserID         primitive.ObjectID `bson:"userID" json:"userID"`
+	UserID         primitive.ObjectID `bson:"userID" json:"userId"`
 	AuthToken      string             `bson:"authToken" json:"authToken"`
 	FCMToken       string             `bson:"fcmToken" json:"fcmToken"`
 	CreatedAt      time.Time          `bson:"createdAt" json:"createdAt"`