[MySQL][PHP]Mysql PDO problem z zapytaniem Opcje

[miras]

Witam, moje zapytanie:

[PHP] pobierz, plaintext 
     $trades = $this->pdo->prepare("SELECT * FROM flip_offers WHERE name = :name AND completed = :completed AND completed_date <= DATE_SUB(NOW(), INTERVAL :interval HOUR");
        $trades->bindParam(":name", $name);
        $trades->bindParam(":completed", $completed);
        $trades->bindParam(":interval", $interval);
        $trades->execute();
[PHP] pobierz, plaintext 

mój błąd:

[XML] pobierz, plaintext 
Fatal error: Uncaught PDOException: SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1 in
[XML] pobierz, plaintext 

Już mnie szlag trafia z tą bazą, podpowie ktoś?