I suggest you get yourself an Amazon Firestick, which Amazon are knocking out at good Black Friday discounts right now.
This will provide your Hitachi not just with Now, but with a whole panoply of other smart apps to choose from.
Set a Payment PIN on your account so that no-one but you can buy memberships on it. Check your bank accounts monthly for any other unexpected payments to Now. That way you can at least nip them in the bud, while you and Now figure out whose fault they are.