Disgusted

I have requested to cancel my contract effective the end of November. They have advised that i require a 30 days notice and that thirty days will be on 2019/12/04, i am now required to pay the full amount on 2019/11/25 (i dont mind) and again on 2019/12/25 for December for only 4 days. I completely understand that i am billed in arrears. What i dont understand is why it is not possible to cancel at the end of November and pay my last debit order on the 25th of November. Ive been dealing with a lot of companies in the past and this is the 1st time that i hear about something as ridiculous as this. Working for a call centre myself i know this request can be actioned it is is literally 4 days into the month. Your call centre is extremely inefficient i escalated my query to 2 different managers and not ine of them were able to assist me. Absolutely ***********!