diff --git a/modules/worker/back/methods/operator/spec/operator.spec.js b/modules/worker/back/methods/operator/spec/operator.spec.js
index 1d4a9a84d..6a8b02e04 100644
--- a/modules/worker/back/methods/operator/spec/operator.spec.js
+++ b/modules/worker/back/methods/operator/spec/operator.spec.js
@@ -3,6 +3,7 @@ const models = require('vn-loopback/server/server').models;
 describe('Operator', () => {
     const authorFk = 9;
     const sectorId = 1;
+    const labeler = 1;
     const notificationName = 'backup-printer-selected';
     const operator = {
         workerFk: 1,
@@ -17,8 +18,10 @@ describe('Operator', () => {
         await models.Operator.create(operator, options);
         return models.NotificationQueue.findOne({
             where: {
-                notificationFk: notificationName
-            }
+                notificationFk: notificationName,
+                authorFk: authorFk,
+            },
+            order: 'created DESC',
         }, options);
     }
 
@@ -27,7 +30,7 @@ describe('Operator', () => {
 
         try {
             const options = {transaction: tx, accessToken: {userId: authorFk}};
-            const notificationQueue = await createOperator(1, options);
+            const notificationQueue = await createOperator(labeler, options);
             const params = JSON.parse(notificationQueue.params);
 
             expect(notificationQueue.notificationFk).toEqual(notificationName);
@@ -59,7 +62,7 @@ describe('Operator', () => {
         }
     });
 
-    it('should not create notification when is already notified', async() => {
+    it('should not create notification when is already notified by another worker', async() => {
         const tx = await models.Operator.beginTransaction({});
 
         try {
@@ -67,18 +70,45 @@ describe('Operator', () => {
             await models.NotificationQueue.create({
                 authorFk: 1,
                 notificationFk: notificationName,
-                params: JSON.stringify({'labelerId': 10, 'sectorId': 10, 'workerId': 10}),
+                params: JSON.stringify({'labelerId': labeler, 'sectorId': sectorId, 'workerId': 10}),
                 created: Date.vnNow(),
             }, options);
 
-            const notificationQueue = await createOperator(1, options);
+            const notificationQueue = await createOperator(labeler, options);
+
+            expect(notificationQueue).toEqual(null);
+
+            await tx.rollback();
+        } catch (e) {
+            await tx.rollback();
+            throw e;
+        }
+    });
+
+    it('should create notification when delay is null', async() => {
+        const tx = await models.Operator.beginTransaction({});
+
+        try {
+            const options = {transaction: tx, accessToken: {userId: authorFk}};
+
+            await models.NotificationQueue.create({
+                authorFk: 1,
+                notificationFk: notificationName,
+                params: JSON.stringify({'labelerId': labeler, 'sectorId': sectorId, 'workerId': 10}),
+                created: Date.vnNow(),
+            }, options);
+
+            const notification = await models.Notification.findOne({where: {name: notificationName}}, options);
+            await notification.updateAttributes({delay: null}, options);
+
+            const notificationQueue = await createOperator(labeler, options);
             const params = JSON.parse(notificationQueue.params);
 
             expect(notificationQueue.notificationFk).toEqual(notificationName);
-            expect(notificationQueue.authorFk).toEqual(1);
-            expect(params.labelerId).toEqual(10);
-            expect(params.sectorId).toEqual(10);
-            expect(params.workerId).toEqual(10);
+            expect(notificationQueue.authorFk).toEqual(authorFk);
+            expect(params.labelerId).toEqual(1);
+            expect(params.sectorId).toEqual(1);
+            expect(params.workerId).toEqual(9);
 
             await tx.rollback();
         } catch (e) {
diff --git a/modules/worker/back/models/operator.js b/modules/worker/back/models/operator.js
index 75ee07821..51fd0bfa1 100644
--- a/modules/worker/back/models/operator.js
+++ b/modules/worker/back/models/operator.js
@@ -15,7 +15,7 @@ module.exports = function(Self) {
             const {userId} = ctx.options.accessToken;
             const {delay} = await models.Notification.findOne({
                 where: {name: notification}
-            });
+            }, options);
             const hasNotified = await models.NotificationQueue.findOne({
                 where: {
                     notificationFk: notification,
@@ -24,10 +24,10 @@ module.exports = function(Self) {
                         {params: {like: '%\"sectorId\":' + instance.sectorFk + '%'}}
                     ]
                 },
-                order: 'CREATED DESC',
-            });
+                order: 'created DESC',
+            }, options);
 
-            if (hasNotified?.created - Date.now() > delay || !hasNotified?.created) {
+            if (hasNotified?.created - Date.now() > delay || !hasNotified?.created || !delay) {
                 await models.NotificationQueue.create({
                     notificationFk: notification,
                     authorFk: userId,