DHL sitting on my parcel, cant deliver, i dont know know what to do.

I am appealing to anyone who can assist me with advice on how to handle the dilema that i am having with DHL. I had a parcel sent from Lusaka Zambia on Friday the 20th of April 2018 with a promise that it will be delivered on Saturday the 21st of April 2018. The reason why i used DHL was because the parcel was VERY urgent and had to be forwaded to a third party here in South Africa on Monday the 23rd of April 2018 by 12:00. I did not recieve the parcel on Saturday as promised, the explanation being that no deliveries are done over the weekend. Come Monday, i was informed that the parcel will be delivered before 12:00pm without fail, no parcel was delivered. Come tuesday, i made several calls and spoke to several guys from the call centre, being transferred from one to the other, holding for more than 10mins everytime am transferred. The promise from morning was that the RAM driver was on his way for delivery. No parcel was delivered because i refused delivery, but why lie about such when i am desperate for that parcel. Today Wednesday, i have been calling since morning and the people who assist me keep on telling me that they are tracking the RAM driver and will call me back, no one ever calls back. The parcel is very sensitive and has already attracted penalties on my side. I dont know what to do anymore as each passing hour is a penalty levied against me. I paid for the parcell in full and do not understand this kind of service. I have used more than R300 on phone calls trying to have my parcel delivered to no avail. If anyone comes across this and have an advice on what i can do to have my parcel please assist me. I am desperate at this stage.