Bad service late delivery always lying

Why is that always i have to complain to receive my parcel i called on Thursday was told if my parcel is not delivered i will get it friday never got my parcel. If i can call them now will be told my parcel is with the driver on his way to deliver but i wont get the parcel. Then there is Tanja who responds to our complaints but still the response takes for ever instead of assisting you as per the response u will be asked to send your details to another email where again you wont get the help you need.