Billing

I joined Rain on the 16 Nov. End of Nov R498 was dedicated from my account. I cancelled the service on the 31 Dec and R499 was deducted. On the 1st of Jan I see Rain was still active. I mailed the billing service and was informed that Rain bill in arrears. I asked then why was a billed for full usage of Rain end of Nov if I only joined on the 16 Nov? I received a mail to ask if the service must be stopped immediately and I responded yes, then I got a mail back saying they cant as billing is from the 1st of each month. My question is why was I billed end of Nov for a full months usage when we only joined the middle of the month and why offer to cancel the service immediately if you cant?