diff --git a/phpBB/phpbb/db/migration/data/v400/remove_jabber.php b/phpBB/phpbb/db/migration/data/v400/remove_jabber.php
index 5ff6b1e9b5..b82fdfc8db 100644
--- a/phpBB/phpbb/db/migration/data/v400/remove_jabber.php
+++ b/phpBB/phpbb/db/migration/data/v400/remove_jabber.php
@@ -101,14 +101,14 @@ class remove_jabber extends migration
 		];
 	}
 
-	public function move_jabber_to_email_notifications(?int $start = 0)
+	public function move_jabber_to_email_notifications(?int $start)
 	{
 		$limit = 1000;
 
 		$sql = 'UPDATE ' . $this->tables['user_notifications'] . '
 			SET ' . $this->db->sql_build_array('UPDATE', ['method' => 'notification.method.email']) . "
 			WHERE method = 'notification.method.jabber'";
-		$this->db->sql_query_limit($sql, $limit, $start);
+		$this->db->sql_query_limit($sql, $limit, $start ?: 0);
 
 		return $this->db->sql_affectedrows() < $limit ? true : $start + $limit;
 	}