How long does 24 hour delivery take??

Delivery from Clicks online is ridiculous!! I placed and order marked for Express delivery (24 hours) on 4 September 2019, it has not been delivered yet today. And when I call the customer care, they say nothing has been done to this order and they can not advise me when anything will be done or when the order will be delivered!! And they will log a call but it will take 2 days to attend to!!! HOW is this applicable to 24 Hour delivery????