Horribly Poor Customer Service!!!

My Samsung S6 was collected over a month ago for a screen repair.I was told by Matshepiso ***) that it would take up to 5 working days to repair.After no feedback after 7 working days I called in to find out what was going on, only to be told it is sitting with a Technician (no other info given).I then phoned in again after 10 working days and they again told me it is still with the technician and they had a backlog on parts?At this point it became horribly frustrating, why does a client have to phone and be kept in the dark?I then eventually called over a week later to find out what was going on to be told that my phone can be delivered.I confirmed delivery for Monday 28/09/15.I was unfortunately not in the office due to personal reasons,I never received any calls about the delivery on Monday.I then spoke to Jenny-Lee from Samsung ADH Premium on Tuesday only to be told that they will only be able to arrange the delivery on Friday(02/10/15) for the next week?She eventually phoned me yesterday to say they can deliver this morning (02/10/15). A device was brought this morning with a different persons contacts and dents and scratches I didn't have on my device!! NOT MY PHONE!!