Why are cellphone numbers added to parcel order details if Dawn Wing's don't use them?

Dawn Wing Kempton Park has the WORST drivers ever. They don't communicate with clients whatsoever. Today (03/05/2019) I was expecting an order but it didn't arrive, I then decided to call the company at around 14:30 to ask about where exactly it is because tracking on the website was going to be a waste of time. I was told that the driver came to my house and hooted but no one was there and they turned back with the order. I asked what time was that because I was home the whole day and didn't hear a hooter or my dogs barking, the lady who was helping me said it was at 11:45. I was then reassured that there'll be an arrangement for the order to be delivered between 18:00-22:00 today but no delivery made.

I honestly do not understand why one fills in their cellphone numbers if drivers are not going to use them and why is there an "additional instructions" box if it's not going to be used.

I need answers because this is not the first time I'm experiencing this. I've been far too patient.