diff --git a/loopback/locale/en.json b/loopback/locale/en.json
index 4b62be2be..b0e33a42f 100644
--- a/loopback/locale/en.json
+++ b/loopback/locale/en.json
@@ -240,5 +240,5 @@
 	"The height must be greater than 50cm": "The height must be greater than 50cm",
 	"The maximum height of the wagon is 200cm": "The maximum height of the wagon is 200cm",
     "The quantity claimed cannot be greater than the quantity of the line": "The quantity claimed cannot be greater than the quantity of the line",
-    "There are tickets for this area, delete them first": "There are tickets for this area, delete them first"
+    "There are tickets to be invoiced for this area, please delete them first": "There are tickets to be invoiced for this area, please delete them first"
 }
diff --git a/loopback/locale/es.json b/loopback/locale/es.json
index 987935c7c..a1d25f77b 100644
--- a/loopback/locale/es.json
+++ b/loopback/locale/es.json
@@ -383,5 +383,5 @@
 	"No valid travel thermograph found": "No se encontró un termógrafo válido",
 	"The quantity claimed cannot be greater than the quantity of the line": "La cantidad reclamada no puede ser mayor que la cantidad de la línea",
 	"type cannot be blank": "Se debe rellenar el tipo",
-    "There are tickets for this area, delete them first": "Hay tickets para esta sección, borralos primero"
+    "There are tickets to be invoiced for this area, please delete them first": "Hay tickets para esta sección, borralos primero"
 }
diff --git a/modules/zone/back/methods/zone/deleteZone.js b/modules/zone/back/methods/zone/deleteZone.js
index 7432475b3..62d88509c 100644
--- a/modules/zone/back/methods/zone/deleteZone.js
+++ b/modules/zone/back/methods/zone/deleteZone.js
@@ -51,9 +51,9 @@ module.exports = Self => {
             };
 
             const ticketList = await models.Ticket.find(filter, myOptions);
-
-            if (ticketList.length > 0)
-                throw new UserError('There are tickets for this area, delete them first');
+            const hasRefFkFilled = ticketList.some(ticket => ticket.refFk !== null && ticket.refFk !== undefined);
+            if (hasRefFkFilled)
+                throw new UserError('There are tickets to be invoiced for this area, please delete them first');
 
             await models.Zone.destroyById(id, myOptions);
 
diff --git a/modules/zone/back/methods/zone/specs/deleteZone.spec.js b/modules/zone/back/methods/zone/specs/deleteZone.spec.js
index aef7fd290..4b67944f3 100644
--- a/modules/zone/back/methods/zone/specs/deleteZone.spec.js
+++ b/modules/zone/back/methods/zone/specs/deleteZone.spec.js
@@ -9,7 +9,7 @@ describe('zone deletezone()', () => {
     };
     const ctx = {req: activeCtx};
     const zoneId = 4;
-    const zoneId2 = 3;
+    const zoneId1 = 1;
     let ticketIDs;
 
     beforeAll(async() => {
@@ -51,13 +51,13 @@ describe('zone deletezone()', () => {
         let error;
         try {
             const options = {transaction: tx};
-            await models.Zone.deleteZone(ctx, zoneId2, options);
+            await models.Zone.deleteZone(ctx, zoneId1, options);
             await tx.rollback();
         } catch (e) {
             error = e.message;
             await tx.rollback();
         }
 
-        expect(error).toEqual('There are tickets for this area, delete them first');
+        expect(error).toEqual('There are tickets to be invoiced for this area, please delete them first');
     });
 });