Changes in Time for delivery when they see it fit for them.

I have bought something from Takealot.com on Sat early morning , there was no option to select a time when the goods should be delivered by as a selected a business address for delivery . I have been tracking the order and there were no updates up until I called in and spoke to an agent , who from his side told me that it was scheduled "deliver before 18H:00" , I am sure that all business are still operating at lower hours at this stage and I can't be held accountable where else the option for time should have been on the website as I was ordering . I can't change the delivery date and would like those goods to be delivered before 4pm today . Please ensure that you upgrade the website so that you can include time slots for people to select , especially the delivery option