Changing delivery date.

When I placed my order it stated the 14th December. Now all of a sudden it says 19th of December. This is unacceptable. There is stock in JHB and I live in Pretoria. And I didn't receive the Same Day Delivery option witch I would have chosen if I could. I would like to know why the date on my delivery changed and why I wasn't given the option of same day delivery. I ordered before 11am.