diff --git a/services/loopback/common/methods/client/updateFiscalData.js b/services/loopback/common/methods/client/updateFiscalData.js
index 37d6677a4..36f7268e8 100644
--- a/services/loopback/common/methods/client/updateFiscalData.js
+++ b/services/loopback/common/methods/client/updateFiscalData.js
@@ -50,7 +50,8 @@ module.exports = Self => {
             'isToBeMailed',
             'hasToInvoiceByAddress',
             'isEqualizated',
-            'isTaxDataVerified'
+            'isTaxDataVerified',
+            'isTaxDataChecked'
         ];
 
         for (const key in params) {
diff --git a/services/loopback/common/methods/sale/updateDiscount.js b/services/loopback/common/methods/sale/updateDiscount.js
index 0201582e0..a46dc1f7d 100644
--- a/services/loopback/common/methods/sale/updateDiscount.js
+++ b/services/loopback/common/methods/sale/updateDiscount.js
@@ -20,7 +20,7 @@ module.exports = Self => {
     });
 
     Self.updateDiscount = async params => {
-        if (isNAN(params.editLines[0].discount))
+        if (isNaN(params.editLines[0].discount))
             throw new Error(`The value should be a number`);
 
         let model = Self.app.models;
@@ -52,7 +52,7 @@ module.exports = Self => {
 
         for (let i = 0; i < params.editLines.length; i++) {
             let currentLine = await model.Sale.findOne({where: {id: params.editLines[i].id}, fields: 'price'});
-            let value = (-currentLine.price * params.editLines[i].discount / 100);
+            let value = ((-currentLine.price * params.editLines[i].discount) / 100);
             await model.SaleComponent.upsert({saleFk: params.editLines[i].id, value: value, componentFk: componentToUse});
 
             await model.Sale.update({id: params.editLines[i].id}, {discount: params.editLines[i].discount});
diff --git a/services/loopback/common/methods/sale/updatePrice.js b/services/loopback/common/methods/sale/updatePrice.js
index b92fdc0ae..5f38d1440 100644
--- a/services/loopback/common/methods/sale/updatePrice.js
+++ b/services/loopback/common/methods/sale/updatePrice.js
@@ -20,7 +20,7 @@ module.exports = Self => {
     });
 
     Self.updatePrice = async params => {
-        if (isNAN(params.price))
+        if (isNaN(params.price))
             throw new Error(`The value should be a number`);
         if (!params.price) params.price = 0;
         let model = Self.app.models;
diff --git a/services/loopback/common/methods/sale/updateQuantity.js b/services/loopback/common/methods/sale/updateQuantity.js
index eac9ac309..5fd66866a 100644
--- a/services/loopback/common/methods/sale/updateQuantity.js
+++ b/services/loopback/common/methods/sale/updateQuantity.js
@@ -25,6 +25,9 @@ module.exports = Self => {
     });
 
     Self.updateQuantity = async(id, quantity) => {
+        if (isNaN(params.editLines[0].discount))
+            throw new Error(`The value should be a number`);
+
         let currentLine = await Self.app.models.Sale.findOne({where: {id: id}, fields: ['quantity']});
         if (quantity > currentLine.quantity)
             throw new Error('The new quantity should be smaller than the old one');