@Anonymous User @gavs82008
Even if you manage to synchronise the renewal dates, you won’t achieve your aim entirely as Now only take one payment a day, so they would come out on the first three business days of the month.
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.