Dpd Laser and Buffalo are very inconsiderate

I ordered on Shein on the 25th of March and have not received my order. My parcel was transferred to a third party, which I wasn't made aware of. I found out when I did my own research. I called the third party is has been transferred to (DPD Laser) and was told they cannot even provide an estimate of delivery. I am utterly disappointed in this as I need the items for an important day to me (graduation), and now I have to make alternative means because of their incompetence, and I do not even know how because graduation is in a week. How can you not provide an estimate? It's basically saying we cannot do anything about it. Inconsiderate to say the least! At this point I'm pushed to even go collect the parcel myself, which is upsetting because I paid for this to be delivered.