Terrible service from DPD Laser

I have received the most appalling service from this courier company. I made a purchase from Shein beginning of December, my parcel was meant to be delivered between the 15th-18th of December, however today is the 22nd of December and I still do not have my parcel with me. The delivery person delivered my parcel on the 17th of December to an incorrect address, she threw the parcel over the fence and I was surprised as I had told her my son is home - however he was not picking up the phone, i then called my nephew who was a few streets away to go home and sign for my delivery. She however didnt wait for his arrival and threw the parcel over the fence. I was shocked to received a message confirming my delivery. when i contacted her she says she threw it over the wall. I then called my nephew as he was now home to confirm the parcel and there was nothing there. I called the driver immediately and told her that there is no parcel, I sent her the location to my house, she then sent me the location to where the parcel was delivered. I informed her that is an incorrect address, I stay at Leondale and she had delivered at Marlons. She said she will speak to her supervisor and they will sort this out. She did manage to retrieve my parcel from the incorrect address the same day and told me that it will be taken over by someone who delivers in my area - the response came after I had been texting her and calling her the whole day as now there was no communication from her side and I was getting worried that maybe she will just leave me in the lurch. I also called the call center and relayed my story. I have spoken to 4 different agents to date and I was promised that my case will be expedited and I will get my parcel on Saturday (20th of Dec), it the 22nd today and still nothing! I am beyond frustrated and highly annoyed as the clothes purchased are for my kids christmas clothes.. so now I do not know what DPD Laser (Ascendia) expects me to do as I do not have a back up plan in terms of me getting other clothes for them. I need my parcel delivered TODAY! I am so sick and tired of calling their call center - you stay on the line for the better half of 30minutes as they are experiencing a high volume of calls! I have made several purchases from Shein and my parcels have always been delivered on time as per estimates time given! This is the first time Shein has used this courier company when delivering my parcel and I never want to use this company ever again! being sent from pillar to post as if I created this mess is totally insane!