phone delivered without complimentary phone cover

I ordered and received a Samsung s6 edge and the phone box states that I am supposed to receive a complimentary/free Samsung phone cover with it which can be redeemed at a Samsung store of original purchase. Since I had ordered the phone telephonically through my vodacom contract upgrade they advised that they(vodacom) are supposed to have provided the phone cover along with the phone upon delivery. There was no cover in the package and when I contacted the upgrade department that I had originally ordered from they advised that I would have to return the entire package along with the phone in order for them to send me a new package that has a phone as well as the complimentary cover in it. I do not understand why I have to be inconvenienced without a cellphone for a period of two weeks or more simply because they cannot make a plan to send me just a phone cover which the wharehouse left out. There is nothing wrong with the phone and it is fully functional. A cover and a cellphone are two separate items that are not dependant on each other. It is not like the phone is missing a battery or a back cover which is attached to it. It is simply missing a complimentary accessory.