Terrible Service

Placed an order on 6 April and received confirmation that it will be delivered on Monday 12 April. Courier arrives on Friday 9 April when I am not available and I asked him to reschedule delivery to Monday 12 April. He agrees and I received the notification via SMS that the delivery will be done before 15h on Monday 12 April. Courier arrives on Saturday 10 April when I am not available. Since it was the second failed delivery the order is cancelled and I am left without the items and Takealot takes 3-5 days to perform the refund. The support person I worked with had limited understanding of the system and could not explain to me why a delivery attempt was made on Saturday when I requested a delivery on Monday (and received confirmation via SMS). She could also not reverse the cancellation to ensure that I can get the items in a realistic time frame. Can you please explain why this happened?