Won't allow me to move my debit order date!!!!

<p>This is preposterous!!!! We have been multichoice clients for YEARS!!!!! I want to simply change my debit order date as I am on a fixed 24 month contract and now I am told even though am paying I cannot change the date and thats that! </p> <p> </p> <p>Someone needs to explain the difference between recieving the money on the 26th vs 25th thats so insane!</p>