Bad Service Postnet

Guys this is by far the worst courier company I've seen. From the word go the service was bad. The sender pay for 48 hours express on the 5th April and I have been waiting from then (today is 11thApril), the lady at the postnet ensure the sender that the parcel wil be delivered not later than Friday. I have been sending emails and still nothing. I don't have words to be honest. All I can say it's **** service!!!