@Anonymous User
Is it your bank refusing payment (e.g. you are over a credit limit or similar), or is it Now refusing it?
If the former, best talk to your bank, rather than Now.
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.
