diff --git a/src/Factories/InvoiceDetailsFactory.php b/src/Factories/InvoiceDetailsFactory.php
index a0c13f9..ee29abb 100644
--- a/src/Factories/InvoiceDetailsFactory.php
+++ b/src/Factories/InvoiceDetailsFactory.php
@@ -25,7 +25,7 @@ class InvoiceDetailsFactory extends Factory
     public function definition(): array
     {
         return [
-            'lineNumber'                   => fake()->unique()->randomNumber(),
+            'lineNumber'                   => fake()->randomDigitNotZero(),
             'recType'                      => fake()->randomElement(RecType::cases()),
             'TaricNo'                      => fake()->bothify('???###??##'),
             'itemCode'                     => fake()->bothify('??##??'),
diff --git a/tests/InvoiceTest.php b/tests/InvoiceTest.php
index dd84cdc..b15cc84 100644
--- a/tests/InvoiceTest.php
+++ b/tests/InvoiceTest.php
@@ -60,7 +60,7 @@ public function test_invoice_validation_fail()
         $invoice = Invoice::factory()->make();
         $invoice->getInvoiceHeader()->setInvoiceType("wrong");
         $invoice->getInvoiceSummary()->setTotalGrossValue(-10);
-
+        
         // "wrong" value will be cast to null because InvoiceType enum does
         // not have "wrong" value.
         // Since null values are stripped from the array, we expect a failure