diff --git a/tests/php-unit-tests/src/BaseTestCase/ItopDataTestCase.php b/tests/php-unit-tests/src/BaseTestCase/ItopDataTestCase.php
index b7c478939f..7be4d9d6be 100644
--- a/tests/php-unit-tests/src/BaseTestCase/ItopDataTestCase.php
+++ b/tests/php-unit-tests/src/BaseTestCase/ItopDataTestCase.php
@@ -1472,7 +1472,7 @@ abstract class ItopDataTestCase extends ItopTestCase
 	 * @return string The unique login
 	 * @throws \Exception
 	 */
-	protected function GivenUserInDB(string $sPassword, array $aProfiles, string $sLogin = null, string &$sUserId = null): string
+	protected function GivenUserInDB(string $sPassword, array $aProfiles, ?string $sLogin = null, ?string &$sUserId = null): string
 	{
 		if (is_null($sLogin)) {
 			$sLogin = 'demo_test_'.uniqid(__CLASS__, true);